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Consumer Products => Avast Free Antivirus / Premium Security (legacy Pro Antivirus, Internet Security, Premier) => Topic started by: Cako on March 25, 2010, 03:08:36 PM

Title: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 25, 2010, 03:08:36 PM
So, I'm not Sherlock Holmes, but after almost two months I finally found out what the real problem with avast.
It's called DPC (Deferred Procedure Calls).
look at the undeniable proof.

Photo 1:
this photo you can clearly see how the DPC is absurdly high, the problem appears only 9 hours after leaving the avast using the scan of P2P shield.
That's what causes the problem of sound and video on youtube and on the computer.
My home PC is connected to 6 days a week 24 hours a day is why I can feel these problems more than others that turn off your PC.
The DPC is extremely high and could have been much higher if I had done more testing for a few hours.


Photo 2:
This picture is clear and transparent what happens when i turn off all the shields of avast, the DPC returns to normal and no sound problems, end more, some times the mouse pointer jumping from one point to another in screen.
I think all avast is causing the high DPC only to be turned on and this problem its worse even more if you use P2P shield or full system scan.

Test the DPC latency.
if you want to test it on your PC just download the DPC Latency Checker in this link:
http://www.thesycon.de/deu/latency_check.shtml
dont need install just download end use,put your tests here,iam using Windows XP/sp3/1G Ram/processor 3.2 pentium 4.

Persistent problem.
this problem with DPC is going on since the final version of avast was launched.
No one from ALWIL want to resolve it, and the worst part is that it must have thousands of users with this same problem and they dont have faintest idea what is avast which is causing sound problems in they computers, sound problems,slow system and the mouse pointer jumping from one point to another in screen.
I do not recommend to exchange of antivirus, avast still the best in the world but version 5 still far from the high reputation of version 4.8.

Solution
If anyone knows the phone of David Copperfield or Houdini please call them to do a magic to FIX this problem.
developers not Seems to be worried with the largest issue of avast at all times.
I hope in the next verssion this error in DPC ends.

if you are a visitor you will only see the photos if you register on the forum, is free,easy end fast.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: wonderwrench on March 25, 2010, 06:56:26 PM
I have XP pro 32 bit sp3 on a Centrino laptop, Intel 1.4 ghz/768 megs of ram, Intel wireless and wired NIC's. I have been trying to reproduce this problem but have not been able to at this point. After 3 days of up time latency is still low. Are you using a P2P app or other similar program?
What NIC are you using? Are you using the latest drivers? If not try updating your NIC drivers and see if you can still reproduce the DPC latency problem.
The reason I say this is I had a PC that had a Realtek NIC running XP using XP's built in driver for the NIC. Though the NIC functioned I had slow downs, stuttering etc. I found the problem using DPC Latency checker, updated the NIC drivers and problem solved. 
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on March 25, 2010, 07:21:58 PM
 ;) will its good that you already find a solution

first time i use it, the dpc pointing driver that going mad

so what is the point testing it at AV?

what i think is, avast is security software and not a device driver

if there is interference try to observe what is the cause of it. and what is the proper testing.

 ;D example: can you try-out swimming so that you will be good boxer  ??? ???  ;D

its the same:
a testing for device driver,  you test it in security software and what you got? interference only and try put another AV it will be the same ratings.

sorry for my words!!! just a point of view

Best Regards!!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 25, 2010, 07:30:02 PM
I have XP pro 32 bit sp3 on a Centrino laptop, Intel 1.4 ghz/768 megs of ram, Intel wireless and wired NIC's. I have been trying to reproduce this problem but have not been able to at this point. After 3 days of up time latency is still low. Are you using a P2P app or other similar program?
What NIC are you using? Are you using the latest drivers? If not try updating your NIC drivers and see if you can still reproduce the DPC latency problem.
The reason I say this is I had a PC that had a Realtek NIC running XP using XP's built in driver for the NIC. Though the NIC functioned I had slow downs, stuttering etc. I found the problem using DPC Latency checker, updated the NIC drivers and problem solved.  

hi.
thanks for reply.
what is NIC. ???
All my drivers are updated.
this problem with the DPC did not happen in version 396.
our friend mut@NT wrote about it in this topic and he is right.
since the 418 version avast has this problem.
read the topic it is very interesting.
http://forum.avast.com/index.php?topic=57146.0
the problem appears after several hours, in my case more than 9 hours of use ..
Yes, I'm using a P2P program, emule, emule had no problems in version 396, but he only advance the problem with the DPC latency.
if you scan your computer with the full scan a few hours you will have this problem (i have).
on my pc the full scan takes up to 2 hours to complete (160 GB HD).
let's see what the support avast will speech.
thanks for the help.
you was very kind.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 25, 2010, 07:39:44 PM
;) will its good that you already find a solution

first time i use it, the dpc pointing driver that going mad

so what is the point testing it at AV?

what i think is, avast is security software and not a device driver

if there is interference try to observe what is the cause of it. and what is the proper testing.

 ;D example: can you try-out swimming so that you will be good boxer  ??? ???  ;D

its the same:
a testing for device driver,  you test it in security software and what you got? interference only and try put another AV it will be the same ratings.

sorry for my words!!! just a point of view

Best Regards!!

its OK,is your point of view,I respect that.
but avast has services installed on the PC and I think also has drivers.
its not a coincidence avast scan a file and DPC latency go almost  to max.
thanks fo reply.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: wonderwrench on March 25, 2010, 07:47:07 PM
;) will its good that you already find a solution

first time i use it, the dpc pointing driver that going mad

so what is the point testing it at AV?

what i think is, avast is security software and not a device driver

if there is interference try to observe what is the cause of it. and what is the proper testing.

 ;D example: can you try-out swimming so that you will be good boxer  ??? ???  ;D

its the same:
a testing for device driver,  you test it in security software and what you got? interference only and try put another AV it will be the same ratings.

sorry for my words!!! just a point of view

Best Regards!!

Hi bong2x, Avast does have drivers as many programs do. Avast uses several filter drivers to be able to scan all needed data. See screen
shot of device manager on my Windows 7 box. To see these devices you must enable show hidden devices from the view menu.
Avast 5 obviously has a conflict with with a device driver some people have on their systems. We just need to find out which device or devices
cause the conflict.

Cako NIC means Network Interface Card or network card.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Zyndstoff (aka Steven Gail) on March 25, 2010, 07:50:37 PM
Hey wonderwrench: it can't be, that you don't have this problem. Cako says that it is a flaw in avast, consequently you must have this latency. If not, it's a bug.  ;D
Maybe you should request a bug-update from alwil?
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: DavidR on March 25, 2010, 07:51:49 PM
Well I decided to download this as a bit of general analysis of my XP Pro SP3 system.

Now I'm just browsing the internet posting on the forums, etc. and it reports "This machine should be able to handle real-time streaming of audio, etc.... without drop-outs," which is patently ridiculous as I'm on dial-up.

So this latency checker has some limitations itself, as it doesn't seem to consider connection speed (or be able to calculate it).
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on March 25, 2010, 07:52:29 PM
thanks for not thinking bad about my post.

try locating the interference by disabling your driver installed if you found it try to download a new build of that driver.

one thing are your automatic window update set at "notify me if there update"?

if you don't update your window it will cause also for the driver going mad and read high dpc rating.

Best regards!!!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: wonderwrench on March 25, 2010, 07:56:24 PM
Hey wonderwrench: it can't be, that you don't have this problem. Cako says that it is a flaw in avast, consequently you must have this latency. If not, it's a bug.  ;D
Maybe you should request a bug-update from alwil?

It is a bug but it may or may not be an Avast 5 bug. It very well might be a device driver bug in a hardware device that causes a conflict with Avast 5.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: wonderwrench on March 25, 2010, 08:00:41 PM
Well I decided to download this as a bit of general analysis of my XP Pro SP3 system.

Now I'm just browsing the internet posting on the forums, etc. and it reports "This machine should be able to handle real-time streaming of audio, etc.... without drop-outs," which is patently ridiculous as I'm on dial-up.

So this latency checker has some limitations itself, as it doesn't seem to consider connection speed (or be able to calculate it).

DPC Latency checker has nothing to do with your internet connection. See link
http://en.wikipedia.org/wiki/Deferred_Procedure_Call
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Zyndstoff (aka Steven Gail) on March 25, 2010, 08:02:20 PM
There are exactly 2 users (two) here in this forum complaining about this symptom. Not more. So I refuse to believe that it is a bug in avast... considering the posts of those 2 users.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 25, 2010, 08:04:22 PM
Hey wonderwrench: it can't be, that you don't have this problem. Cako says that it is a flaw in avast, consequently you must have this latency. If not, it's a bug.  ;D
Maybe you should request a bug-update from alwil?

It is a bug but it may or may not be an Avast 5 bug. It very well might be a device driver bug in a hardware device that causes a conflict with Avast 5.
wonderwrench tanks again end ignore this user it just mess it up.( Zyndstoff)
Network Interface Card its Ok end updated.
my computer is always updated with everything, that's why I'm not going back to using version 396.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: YoKenny on March 25, 2010, 08:06:38 PM
On my XP Pro system my connection looks like DavidR's connection but on my Windows 7 system it shows DPC latency errors.  ???

Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Zyndstoff (aka Steven Gail) on March 25, 2010, 08:07:40 PM
Whatever  ;D
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on March 25, 2010, 08:12:40 PM
ok wonderwrench i am thank you for introducing that testing
with that i did locate what is the problem in my computer
do you remember i say that i got the same peak value?
its just because my PC Suit Nokia driver is too old that is why i got that higher ratings
i change my Nokia Driver now its calm down no high DPC ratings


Best Regards!!!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: wonderwrench on March 25, 2010, 08:20:50 PM
Hey wonderwrench: it can't be, that you don't have this problem. Cako says that it is a flaw in avast, consequently you must have this latency. If not, it's a bug.  ;D
Maybe you should request a bug-update from alwil?

It is a bug but it may or may not be an Avast 5 bug. It very well might be a device driver bug in a hardware device that causes a conflict with Avast 5.
wonderwrench tanks again end ignore this user it just mess it up.( Zyndstoff)
Network Interface Card its Ok end updated.
my computer is always updated with everything, that's why I'm not going back to using version 396.

Question: How do you check to see if your drivers are up to date? Windows update? System or motherboard manufacturer? Non of these will insure you have the latest drivers. What NIC does your PC have. The problem you are having could be related to any device driver on your PC. To find the cause people having this problem need to list the hardware in there systems and see if any are common to all having this problem.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Zyndstoff (aka Steven Gail) on March 25, 2010, 09:07:11 PM
Cako doesn't need to check anything. He knows that it is avast's problem and fault.
He knows!
 ;D
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: RejZoR on March 25, 2010, 09:18:38 PM
I'm watching a movie and it's still all green. avast! is fully enabled of course. Vista x64...
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: calcu007 on March 26, 2010, 12:24:06 AM
He thinks he knows
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on March 26, 2010, 12:40:55 AM
Try to use Device Doctor (Device Driver Updater) to confirm the drivers are up to date.
http://www.devicedoctor.com/

Not perfect, but may help some...
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 26, 2010, 12:48:58 AM
Hey wonderwrench: it can't be, that you don't have this problem. Cako says that it is a flaw in avast, consequently you must have this latency. If not, it's a bug.  ;D
Maybe you should request a bug-update from alwil?

It is a bug but it may or may not be an Avast 5 bug. It very well might be a device driver bug in a hardware device that causes a conflict with Avast 5.
wonderwrench tanks again end ignore this user it just mess it up.( Zyndstoff)
Network Interface Card its Ok end updated.
my computer is always updated with everything, that's why I'm not going back to using version 396.

Question: How do you check to see if your drivers are up to date? Windows update? System or motherboard manufacturer? Non of these will insure you have the latest drivers. What NIC does your PC have. The problem you are having could be related to any device driver on your PC. To find the cause people having this problem need to list the hardware in there systems and see if any are common to all having this problem.

well.
I have few programs with drivers in my PC, myself download and upgrade all.
I deactivated several drivers and devices, even uninstalled the motorola one and the problem with high DPC latency continues.
My Windows update its on,end working -all updates.
motherboard  asus.-all driver updates ...
I I used my device manager, there no conflict.
i disable multiple devices , and the problem continues.
I get the last 3 hours doing this and i dont found nothing,all versions of drivers who I use are in accordance with the manufacturers.
i dont use cracks in my softwares.
how you could find the exactly driver who was giving this problem to you ???  ???
you are one of the few here who really believe in helping.
as you can see what they write here, unfortunately not all have the same inteded to help.
thanks. :)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 26, 2010, 12:52:11 AM
Try to use Device Doctor (Device Driver Updater) to confirm the drivers are up to date.
http://www.devicedoctor.com/

Not perfect, but may help some...
thanks, i will install now.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 27, 2010, 02:52:29 PM
personally I I spent my time in the latest 27 hours doing tests on my computer.
I installed the Device Doctor and guess what, any driver needs to be installed or updated.
I uninstall Avast 5 end install Avast 4.8 (latest version)
Avast 4.8 - low DPC latency.
I uninstall avast 4.8 and install kaspersky.
kaspersky - low DPC latency.
I uninstall kaspersky and install AVG.
AVG - low DPC latency.
I uninstall AVG and install Avast 5 version 396.
Avast 5 version 396 - low DPC latency.
I uninstall Avast 5 version 396 end install Avast 5 version 462.
Avast 5 version 462 - very high DPC latency. >:(
when I deactivated the P2P shield scan - low DPC latency.
well, the only thing left to do its downgrade the drivers, but I will not do.
I'm using Avast 5 version462.

My sister's computer:
have the exactly same result.
her computer has a conf. completely different from mine.

Next version of avast.
I'll wait for the next version and see if the problem continues, I will create another topic again, end again,end again , end again, end again..........
thank for everything guys.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: dabeniao on March 27, 2010, 04:04:13 PM
I use Windows Vista HomePremium SP2, with Limewire and uTorrent (Sorry, don't like emule  :P)

No matter I open the P2P programs, with (7) avast! shields on or off,  I see no difference on the DPC value.

Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on March 27, 2010, 05:21:03 PM
I'll run eMule and uTorrent for test, but don't expect much... because my internet provider doesn't allow us to use P2P system and I can't download any file via P2P even Openoffice.org installer :'(
I can only run these software without connection (even so P2P shield scans something... it counts now thousands files total :o)

I can't find any change about P2P shield between 5.0.396 to 5.0.462, so this problem is completely beyond me :-\
I hope your problem will be solved...

Best wishes
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 27, 2010, 05:31:08 PM
I'll run eMule and uTorrent for test, but don't expect much... because my internet provider doesn't allow us to use P2P system and I can't download any file via P2P even Openoffice.org installer :'(
I can only run these software without connection (even so P2P shield scans something... it counts now thousands files total :o)

I can't find any change about P2P shield between 5.0.396 to 5.0.418, so this problem is completely beyond me :-\
I hope your problem will be solved...

Best wishes

hi, thanks again for the tip about Device Doctor.
so, this problem appears only after a few hours.
let avast scan the files of emule for 9 hours or more and check the DPC latency.
I hope fix this problem one day.
thanks again.. :D
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: wonderwrench on March 27, 2010, 06:56:53 PM
personally I I spent my time in the latest 27 hours doing tests on my computer.
I installed the Device Doctor and guess what, any driver needs to be installed or updated.
I uninstall Avast 5 end install Avast 4.8 (latest version)
Avast 4.8 - low DPC latency.
I uninstall avast 4.8 and install kaspersky.
kaspersky - low DPC latency.
I uninstall kaspersky and install AVG.
AVG - low DPC latency.
I uninstall AVG and install Avast 5 version 396.
Avast 5 version 396 - low DPC latency.
I uninstall Avast 5 version 396 end install Avast 5 version 462.
Avast 5 version 462 - very high DPC latency. >:(
when I deactivated the P2P shield scan - low DPC latency.
well, the only thing left to do its downgrade the drivers, but I will not do.
I'm using Avast 5 version462.

My sister's computer:
have the exactly same result.
her computer has a conf. completely different from mine.

Next version of avast.
I'll wait for the next version and see if the problem continues, I will create another topic again, end again,end again , end again, end again..........
thank for everything guys.


Is is possible build 396 did not scan P2P traffic but 462 does? Kato: was there activity in the P2P graph using build 3.96? You say your sisters PC is also downloading P2P using eMule? Do other P2P programs also exhibit the same problem? If not it could be a conflict between eMule and Avast 5. What happens if you close or pause eMule? does this also fix the DPC latency problem or does it stay the same?
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 27, 2010, 07:27:55 PM
hi wonderwrench.
Quote
Is is possible build 396 did not scan P2P traffic but 462 does? Kato: was there activity in the P2P graph using build 3.96?
no.
avast is scanning the emule, I saw the graphics.

Quote
You say your sisters PC is also downloading P2P using eMule?
yes,she has emule end avast its scanning.(not now, eMule is disabled to not have problems with the sound.)

Quote
Do other P2P programs also exhibit the same problem?
well.i have 3,emule,utorrnte end limewire.
i test emule end utorrent -high DPC latency-

Quote
If not it could be a conflict between eMule and Avast 5,What happens if you close or pause eMule
I thought about it, but because the 396 version dont has it.
when I turn off the emule the graphic of P2P of avast version 462  stop end i have low DPC latency.

Quote
does this also fix the DPC latency problem or does it stay the same?
I did not sleep, I was very tired and turned off my PC, I need a few hours with avast scaning the P2P for testing limewire and pause emule.

I've never seen this in my life.
I understand something about computers, but is the first time I see a problem like that.

Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on March 28, 2010, 01:59:04 PM
I'm afraid I failed to reproduce your problem... even after about 20 hours DPC Latency Checker doesn't show any peek.
It seems this problem occurs only in XP, so maybe this is the reason I failed... I use Vista :P
I also run uTorrent in XP compatibility mode but no effect. Only I noticed is a bit increase of sound chattering when a load has been added to my PC.

What happening in your P2P shield... got me stumped.  :-\

Again I hope your problem will be solved. Best wishes
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on March 28, 2010, 02:58:52 PM
i have peak ratings what is that mean?
its coming back this morning.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 28, 2010, 03:25:00 PM
I'm afraid I failed to reproduce your problem... even after about 20 hours DPC Latency Checker doesn't show any peek.
It seems this problem occurs only in XP, so maybe this is the reason I failed... I use Vista :P
I also run uTorrent in XP compatibility mode but no effect. Only I noticed is a bit increase of sound chattering when a load has been added to my PC.

What happening in your P2P shield... got me stumped.  :-\

Again I hope your problem will be solved. Best wishes

this sound chattering is what I have on my PC when the DPC latency is too high.
Your pick was not red, but it was enough for you see what happens on my pc with my sound (sound chattering).
I think many people have the same problem and do not realize.
I'll keep trying and insisting on a solution.
you are the best. :D
thank you for testing and your dedication.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 28, 2010, 03:27:53 PM
i have peak ratings what is that mean?
its coming back this morning.


this is just the beginning my friend, after many hours it gets worse.
My PC is turned on, 6 days a week 24 hours a day, so I see the problem as DPC latency more easier.
are you having problems with sound ?
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Romberry on March 28, 2010, 03:39:27 PM
Well I decided to download this as a bit of general analysis of my XP Pro SP3 system.

Now I'm just browsing the internet posting on the forums, etc. and it reports "This machine should be able to handle real-time streaming of audio, etc.... without drop-outs," which is patently ridiculous as I'm on dial-up.

So this latency checker has some limitations itself, as it doesn't seem to consider connection speed (or be able to calculate it).

I don't think you have a firm grasp on what DPC latency is. It has absolutely nothing to do with internet connection bandwidth. DPC latency is a measurement of delays (latency) that occur within the computer system in something called "Deferred Procedure Calls." See http://en.wikipedia.org/wiki/Deferred_Procedure_Call for more info, and also see the MSDN definition at http://msdn.microsoft.com/en-us/library/ms789534.aspx

The message from DPC checker telling you "This machine should be able to handle real-time streaming of audio, etc.... without drop-outs" is not saying that your connection to the next can handle/support these things, it's saying that your computer hardware itself can handle/support these things. See the difference?
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on March 28, 2010, 03:46:02 PM
 :D i run it while im playing internet radio for 1 hour only :D

but you know try also to figure out what the problem in your system and if you got it you may share here with everybody. playing sound its ok low noise :D

Best Regards!!!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: DavidR on March 28, 2010, 04:22:30 PM
<snip>
I don't think you have a firm grasp on what DPC latency is. It has absolutely nothing to do with internet connection bandwidth. DPC latency is a measurement of delays (latency) that occur within the computer system in something called "Deferred Procedure Calls."<snip>

The message from DPC checker telling you "This machine should be able to handle real-time streaming of audio, etc.... without drop-outs" is not saying that your connection to the next can handle/support these things, it's saying that your computer hardware itself can handle/support these things. See the difference?

My grasp of it is sufficient, what I left out was the tongue in cheek smiley from my post.

The point I was too subtly trying to make is, that any DPC Latency measurement and the ability to download, play media, multi-task, etc. is dependant on more that the reporting of one set of figures. There are obviously other factors going on in the OPs system causing this drag in DPC latency. Something that many people have been banging on about for some considerable time.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: calcu007 on March 28, 2010, 08:16:27 PM
The OP appears want a Avast version that works in his computer 100% without problems. He dont understand that there are not perfect programs. How are you sure that the latency problem is caused by Avast and not for other program or driver? Stop whining and re-check your problem before blame avast.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 28, 2010, 09:29:43 PM
The OP appears want a Avast version that works in his computer 100% without problems. He dont understand that there are not perfect programs. How are you sure that the latency problem is caused by Avast and not for other program or driver? Stop whining and re-check your problem before blame avast.

hi, I do not agree,Avast was working 100% on my PC.
since version 418 does not work 100%.
I dont want anything perfect, but if you had this problem, you would be very upset too.
I did the possible.
I can only point the problem now, fix is much more difficult.
see the first two photos of the topic, you will see the difference between the avast (P2P shield) on and off.

this problem has nothing to do with the Internet, is a problem with drivers...
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Antarctica on March 28, 2010, 11:02:55 PM
The OP appears want a Avast version that works in his computer 100% without problems. He dont understand that there are not perfect programs. How are you sure that the latency problem is caused by Avast and not for other program or driver? Stop whining and re-check your problem before blame avast.

hi, I do not agree,Avast was working 100% on my PC.
since version 418 does not work 100%.
I dont want anything perfect, but if you had this problem, you would be very upset too.
I did the possible.
I can only point the problem now, fix is much more difficult.
see the first two photos of the topic, you will see the difference between the avast (P2P shield) on and off.

this problem has nothing to do with the Internet, is a problem with drivers...


Cako, I don't understand you... Why do you insist of running Avast on your computer? See myself it was Avira that would not run nicely on my box, and you agree that Avira is not a bad AV either, right? Now since I did install Avast Internet Security, all my problems are gone. There are thousand of different PC with different configurations, it's almost impossible that a certain AV will work perfectly with every configuration! Just pick up another AV on I am sure your problems will be gone. ;)
Good luck!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: calcu007 on March 29, 2010, 01:23:00 AM
The OP appears want a Avast version that works in his computer 100% without problems. He dont understand that there are not perfect programs. How are you sure that the latency problem is caused by Avast and not for other program or driver? Stop whining and re-check your problem before blame avast.

hi, I do not agree,Avast was working 100% on my PC.
since version 418 does not work 100%.
I dont want anything perfect, but if you had this problem, you would be very upset too.
I did the possible.
I can only point the problem now, fix is much more difficult.
see the first two photos of the topic, you will see the difference between the avast (P2P shield) on and off.

this problem has nothing to do with the Internet, is a problem with drivers...


They are not problems. Also lot members gave you alternatives to solve YOUR complaints. These situations with Avast bothers you, then change the AV or live with it. The live is NOT perfect. That some users maybe 1 or 2, comparable with millions of Avast users, had YOUR complaints, doesnt mean that is a Avast problem.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: faust on March 29, 2010, 11:29:56 AM
Great; another thread that has been ruined by fanboys who don't understand the concept of bug reporting.

If only fanboys could be moved to the virus vault, this forum might actually be useful again.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Vlk on March 29, 2010, 11:50:12 AM
Sorry but you're not right in this case, faust.

I spent a great deal of time trying to simulate the problem and/or find an issue in the avast driver sources that could lead to this scenario (e.g. holding spinlocks for too long etc). And I'm pretty confident that the problem is not related to avast in this case.

As you can easily check, cako is spending a lot of time complaining about this issue here (pretty much all of his ~100 posts so far are related to this). But the problem is, the measurements are inconsistent. Also, it simply doesn't make sense that 5.0.462 would have this problem while the previous versions not have it as there were no meaningful changes that could make any difference. DPC Latencies are difficult to debug, and you usually need to understand what's really going on under the hood to be able to understand the problem.

Now on a side note, we've just found that the paid version of Malwarebytes (namely its "IP Protection" component) is a real DPC Latency master though (we see *huge* latencies when doing e.g. speed tests with IP Protection enabled). And for some reason, it gets ever worse when avast is installed (I suppose that's because with avast's WebShield in place, the connections are doubles [as WebShield acts as a HTTP proxy]).
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Yezinki on March 29, 2010, 12:01:51 PM
Vlk,so you suggest to run MBAM resident with out IP Protection with Avast 5 Free, to reduce DPC latency......is that correct?

Regards!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Vlk on March 29, 2010, 12:26:49 PM
Well see for yourself, I wrote a bit more about it here: http://forum.avast.com/index.php?topic=56694.msg486878#msg486878
If this is happening even on your system (it will depend on your connection speed - here I have a ~60 mbit connection so pretty fast) you should get in touch with MBAM and report the issue to them.

It should be relatively easy to fix on their side, I assume they're doing lookups to the banned IP list on DPC level (e.g. while holding a spinlock) while this is not really needed.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on March 29, 2010, 01:19:51 PM
Two local proxy problem... if so, it is possible that this causes my sound chattering (only sometimes, indeed), because I use another local proxy (Proxomitron).
My sound chattering is always on my PC (long running worsens this), and avast! and Proxomitron is always together too... I thought chattering is because my PC's power shortage, but it seems this is the reason.

Now DPC Latency Checker shows exactly same graph compared to before my post, and this time is only 1 hours after reboot (with no P2P application).
Cako, are you using other local proxy software? If so, it can cause your problem too.

Anyway, I like avast very much. Thanks Vlk for your great work!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 29, 2010, 04:36:57 PM
Sorry but you're not right in this case, faust.

I spent a great deal of time trying to simulate the problem and/or find an issue in the avast driver sources that could lead to this scenario (e.g. holding spinlocks for too long etc). And I'm pretty confident that the problem is not related to avast in this case.

As you can easily check, cako is spending a lot of time complaining about this issue here (pretty much all of his ~100 posts so far are related to this). But the problem is, the measurements are inconsistent. Also, it simply doesn't make sense that 5.0.462 would have this problem while the previous versions not have it as there were no meaningful changes that could make any difference. DPC Latencies are difficult to debug, and you usually need to understand what's really going on under the hood to be able to understand the problem.

Now on a side note, we've just found that the paid version of Malwarebytes (namely its "IP Protection" component) is a real DPC Latency master though (we see *huge* latencies when doing e.g. speed tests with IP Protection enabled). And for some reason, it gets ever worse when avast is installed (I suppose that's because with avast's WebShield in place, the connections are doubles [as WebShield acts as a HTTP proxy]).

vlk.
Sorry but you're not right in this case, vlk.
faust its absolutely right, this is a site for support or not.
I'm proud of my 100 posts because I dont quit when someone says no, or i see a problem, or when someone say that is impossible, I try, I fight I win.
thought it would be like if everyone gave up the first problem ...
if someone says "this is impossible",just fight end make it "possible",the persistence leads to success ...
why you dont say you did tests about the problem,I probably would not have written 100 posts.
I never said avast is a bad antivirus, he is the best, so I still use.
the sound problem on my PC is resolved by placing the emule (version 0.49c) on exceptions's list of  P2P shield.
i will update the emule soon end test again...
I insist on a permanent solution if it exists on my PC,and i dont understand how the 396 version its so perfect on my PC.
well,vlk I think you really dont like me, that's why you did not write directly to me.
anyway,thanks for trying simulate the problem.

and guys, stop asking me to change antivirus I will not do that, and I will buy AIS5.
just change antivirus is a coward solution.

NON
I'm not using any proxy software.
i dont use Malwarebytes,i use Spybot  - Search & Destroy (without real-time protection)
but probably have something on my PC and the sisterr's PC who may be in conflict with avast (but why  the 396 version dont have conflict ??? its a mystery.)
My modem is routed is a dslink 260e, my sister also.
the modem have a firewall, is there any chance of avast to be difficult to receive or scan the information packets of modem ???
avast probably conflicts with something on some PCs.
on my PC just happens when avast scan emule (utorrent) with the P2P shield,end i have the sound problems.
when I turn off P2P shield or place the emule (version 0.49c) on exceptions's list of  P2P shieldthe my sound and avast work perfectly.
you find the source of your problem  ???
in your case is a proxy software. ???
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on March 29, 2010, 05:32:29 PM
I googled about DPC latency and P2P application... found some articles. If you have seen these before, then sorry for disturbing.

1.
http://www.thefreewindows.com/?p=2497
This article says eMule has DPC Latency problem itself... and I can't find any information about DPC latency in recent eMule changelog.
Perhaps this issue isn't fixed yet, and appears in some situation (with avast 5.0.462 :( ).

2.
http://forum.utorrent.com/viewtopic.php?pid=468852
This forum users have DPC Latency problem with uTorrent and Microsoft Security Essentials... and they say shutting down one of these software resolves the problem immediately.

Please try to shut down P2P application or disable and re-enable avast!'s P2P shield when the problem happens. Does it show any change? After doing this, DPC Latency Checker still shows any peak?
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Zyndstoff (aka Steven Gail) on March 29, 2010, 06:03:29 PM
I hope Cako's problems will be solved soon. He really is suffering.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Vlk on March 29, 2010, 06:04:46 PM
Chill down Zyndstoff, you seem to be learning fast from Logos... ;)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Zyndstoff (aka Steven Gail) on March 29, 2010, 06:06:48 PM
Sorry, you are right.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 29, 2010, 08:14:19 PM
I googled about DPC latency and P2P application... found some articles. If you have seen these before, then sorry for disturbing.

1.
http://www.thefreewindows.com/?p=2497
This article says eMule has DPC Latency problem itself... and I can't find any information about DPC latency in recent eMule changelog.
Perhaps this issue isn't fixed yet, and appears in some situation (with avast 5.0.462 :( ).

2.
http://forum.utorrent.com/viewtopic.php?pid=468852
This forum users have DPC Latency problem with uTorrent and Microsoft Security Essentials... and they say shutting down one of these software resolves the problem immediately.

Please try to shut down P2P application or disable and re-enable avast!'s P2P shield when the problem happens. Does it show any change? After doing this, DPC Latency Checker still shows any peak?
I did what you said..the pictures (taked 4 hours after p2p scan emule) dont have quality,but is visible,and my modem has IP filter.
I just test the limewire right now end happened the same with him (high DPC latency).
I found this:
https://forums.comodo.com/bug-report-cis/cis-40x-still-causing-high-dpc-latency-issue-t54242.0.html
end this:
http://forum-en.msi.com/index.php?topic=132050.msg994534

if microsoft secure essential,avast end comodo internet security has the same problem, it must be very difficult of identify and fix,I think these programs conflict between one and more drivers or something in this computers, but what?.
I dont install beta programs on my PC, when emule is in the final version I'll install end try make tests again, now emule is in 0.50a beta 2 i'am using version 0.49c final.
thanks for the links.

Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Zyndstoff (aka Steven Gail) on March 29, 2010, 08:25:51 PM

if microsoft secure essential,avast end comodo internet security has the same problem, it must be very difficult of identify and fix,I think these programs conflict between one and more drivers or something in this computers, but what?.
I dont install beta programs on my PC,


See, Cako, now you're talking right stuff.  ::) That is exactly the way the problem goes. Drivers for hardware are written in a sloppy way, hardware has it's problems. Sometimes is just the specific combination of hardware, drivers and software that just won't fit together 100%. Every single part, taken on it's on, is perfectly ok, but the unique combination just won't go.
BTW: I think that in most of the cases it's the driver side, that launches the problem - drivers are most often programmed in a hasty way and very, very often they don't adhere 100% to agreed specifications.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: calcu007 on March 30, 2010, 02:22:42 AM
Well, this Cako dont learns, even with VLK, the main developer, he dare  tell VLK is wrong. Hey CAKO, you want to develops Avast, do you know to fix the problem? I dont think so.....
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on March 30, 2010, 02:34:00 AM
Great software :o

From Comodo support forum:
https://forums.comodo.com/bug-report-cis/comodo-uses-to-much-system-resources-t34562.0.html;msg304996#msg304996

See image, you can identify which drivers causes high DPC Latency!
This app is contained Windows 7 SDK -> Windows Development Tools

Edit: correct typo

---------------------

I feel this is so-called "compatibility" problem... same program shows different result on different environment.

And one other thing, "latest" doesn't mean "good".  One of my friends had a trouble with graphic driver, and version down to 2 before release solve the problem.

So I suggest this: I know you don't like to do this, but return back to .396 for the time being, and wait for some ways appear... there are a good few people having similar problem, and if one of these problem successfully solved, it can be applied to yours.

P.S.
Did you already try to disable all resident software (from msconfig) except avast and run emule? If it works fine, the problem is caused by some of your resident software.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Vlk on March 30, 2010, 10:21:39 AM
We use xperf as part of our routine testing. It's one of the good tools in the Windows Driver Kit (WDK) that help developers debug these kind of issues.

Of course, if cako is willing to use the tool to find out what's causing the peaks on his system, it would be welcome.

Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Rednose on March 30, 2010, 10:30:56 AM
To be honnest : I would be surprised :-\

Greetz, Red.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: YoKenny on March 30, 2010, 02:58:41 PM
I found this interesting:
Turn off indexing and speed up Windows XP
http://lifehacker.com/031440/turn-off-indexing-and-speed-up-windows-xp

I do not have indexing enabled on my XP system but I do on my Windows 7 system.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: smudger on March 30, 2010, 06:01:10 PM
I found this interesting:
Turn off indexing and speed up Windows XP
http://lifehacker.com/031440/turn-off-indexing-and-speed-up-windows-xp

I do not have indexing enabled on my XP system but I do on my Windows 7 system.

Thanks a lot for the link (and the link it links to)      8)

smudge
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 30, 2010, 06:25:01 PM
Great software :o

From Comodo support forum:
https://forums.comodo.com/bug-report-cis/comodo-uses-to-much-system-resources-t34562.0.html;msg304996#msg304996

See image, you can identify which drivers causes high DPC Latency!
This app is contained Windows 7 SDK -> Windows Development Tools

Edit: correct typo

---------------------

I feel this is so-called "compatibility" problem... same program shows different result on different environment.

And one other thing, "latest" doesn't mean "good".  One of my friends had a trouble with graphic driver, and version down to 2 before release solve the problem.

So I suggest this: I know you don't like to do this, but return back to .396 for the time being, and wait for some ways appear... there are a good few people having similar problem, and if one of these problem successfully solved, it can be applied to yours.

P.S.
Did you already try to disable all resident software (from msconfig) except avast and run emule? If it works fine, the problem is caused by some of your resident software.
I found the download of RATTV3,my computer restart if I do the test now will not show anything
avast its scanner emule again,in a few hours the problem will appear end I will use the program.
NON, you can put the link of the program that you are using here.

YoKenny
I've tried it, cleaned the registry uninstall programs and no fix it.
thanks for the suggestion.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on March 31, 2010, 01:56:22 AM
Sorry for late response.

I found the download of RATTV3,my computer restart if I do the test now will not show anything
avast its scanner emule again,in a few hours the problem will appear end I will use the program.
NON, you can put the link of the program that you are using here.

You can download Windows7 SDK from here.
http://www.microsoft.com/downloads/details.aspx?FamilyID=c17ba869-9671-4330-a63e-1fd44e0e2505&displaylang=en

It's a web based installer, so download and run it. Installer will start, and install Windows Development Tools.
After installation, you can see a short-cut in Start menu says "Install Windows Performance Analysis Tools" (or the like). Install.

Usage, here the quote from Comodo forum:
Quote
<snip>
4. Open a command prompt (elevated if necessary) and navigate to the xperf folder the default is "C:\Program Files\Microsoft Windows Performance Toolkit"

5. For the sake of simplicity type:

 xperf -on DiagEasy and press return.

This will begin the trace. I suggest letting it run for several minutes to ensure you capture the details required.

6. After a time has passed type :

xperf -d trace.etl and press return.

This will stop the trace.

7. Type:

xperf trace.etl and press return.

This will display the results. We could have collected more specific data but using the DiagEasy switch is good enough for our purposes.

8. Scroll down to the section headed DPC CPU Usage.

9. Select a nice big spike, this corresponds to the spikes you will have observed in DPC latency checker. Select the spike and right click. From the menu select Summary Table. This will open a new window with details regarding drivers. The higher the value the more problematical the driver.
<snip>

In fact, most of my DPC Latency is caused by "USBPORT.sys" and "ataport.sys" ???
Port controller driver? I should google for my problem again  :(

Good luck!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 31, 2010, 03:04:00 PM
my friend I need pray more..
since yesterday I've been trying to do this program work but i cant, this program (Install Windows Performance Analysis Tools) does not install on my xp
it dont install this files on my xp.
GPUView
HeapAction_CullFunctionsExample.txt
KernelTraceControl.dll
KernelTraceControl.h
README.txt
WPF Performance Suite - installed
WaitClassification_ImportantThreadStartFunctions.t xt
WaitClassification_WatchFunctions.txt
WaitClassification_WatchLocks.txt
WindowsPerformanceToolkit.chm
dbghelp.dll
hwpower2etw.exe
hwpower2etw.ini
perf_heap.dll
perf_nt.dll
perf_nt_c.dll
perf_nt_g.dll
perf_onoff.dll
perf_onoff_c.dll
perf_onoff_g.dll
perf_tdh.dll
perfcore.dll
perfcore.ini
perfctrl.dll
perfg.dll
symsrv.dll
xbootmgr.exe
xbootmgr.log
xbootmgrSleep.exe
xperf.exe
xperfview.exe
I'll keep looking for it or try something else.
(http://i43.tinypic.com/w9af42.jpg)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on March 31, 2010, 04:26:31 PM
my friend I need pray more..
since yesterday I've been trying to do this program work but i cant, this program (Install Windows Performance Analysis Tools) does not install on my xp
<snip>
I'll keep looking for it or try something else.

I'm afraid I found a sad article...
http://blogs.microsoft.co.il/blogs/sasha/archive/2008/03/15/xperf-windows-performance-toolkit.aspx
Quote
First of all, you need to install it from WHDC.  Note that the installation is only supported on Windows Vista SP1 and Windows Server 2008 (I got it to be almost fully functional without Vista SP1, but caveat emptor).  Data collection can be performed on a Windows XP SP2 or Windows Server 2003 system (you only need xperf.exe and perfctrl.dll for that), but the trace decoding can only be performed on NT 6.0 and higher.
:'( :'( :'( :'( :'(

Do you have Vista/7 PC?
If not, I'll upload these 2 files to somewhere (I already sent a personal message to you, because I think this is my last post today...), and if you don't mind, I'll see what driver causes your problem.
I'm not an expert but only a normal PC user, so maybe I can do is seeing the driver's filename. :-\

I know it contains some your personal information (process names, or such?) , but if you don't mind...
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 31, 2010, 06:59:15 PM
my friend I need pray more..
since yesterday I've been trying to do this program work but i cant, this program (Install Windows Performance Analysis Tools) does not install on my xp
<snip>
I'll keep looking for it or try something else.

I'm afraid I found a sad article...
http://blogs.microsoft.co.il/blogs/sasha/archive/2008/03/15/xperf-windows-performance-toolkit.aspx
Quote
First of all, you need to install it from WHDC.  Note that the installation is only supported on Windows Vista SP1 and Windows Server 2008 (I got it to be almost fully functional without Vista SP1, but caveat emptor).  Data collection can be performed on a Windows XP SP2 or Windows Server 2003 system (you only need xperf.exe and perfctrl.dll for that), but the trace decoding can only be performed on NT 6.0 and higher.
:'( :'( :'( :'( :'(

Do you have Vista/7 PC?
If not, I'll upload these 2 files to somewhere (I already sent a personal message to you, because I think this is my last post today...), and if you don't mind, I'll see what driver causes your problem.
I'm not an expert but only a normal PC user, so maybe I can do is seeing the driver's filename. :-\

I know it contains some your personal information (process names, or such?) , but if you don't mind...
i just have the windows xp,i will update to windows 7 soon. :D
I dont know what to say to thank, but I tried put all the files and did not work, windows xp does not accept commands to the xperf, I could not trace,i try everything.
i put the 2 files o c:\  end C:\Program Files\Microsoft Windows Performance Toolkit end try start experf.exe end i use the cmd
I use rattv3, it also tracks the dpc.
I'll put this photo here.
later I'll search the drivers suspicious.
i upload the log file heare.
http://uploading.com/files/82c54f59/cswa-accumulator-report.zip/
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on March 31, 2010, 08:42:48 PM
probably one of the suspects drivers are responsible for the high DPC latency on my PC.
tcpip.sys
VIDEOPRT.SYS
Ndis.sys

end a driver was classified as Unknown.
the most suspect that is conflicting with avast I think it's the tcpip.sys
the problem happening with DPC using P2P shield.
I'll keep looking.
NON.
you fix your problem ?
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: coolsilver on April 01, 2010, 02:38:37 AM
My guess whatever is causing your issue will be gone when you upgrade to Windows 7.

Who are the publishers of those files in the file properties? Are they Microsoft driver files or replaced by something else?
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on April 01, 2010, 06:43:21 AM
probably one of the suspects drivers are responsible for the high DPC latency on my PC.
tcpip.sys
VIDEOPRT.SYS
Ndis.sys

<snip>
NON.
you fix your problem ?

Not yet.

tcpip.sys appears in my list too, and it causes high DPC Latancy. Ndis.sys also appears, but it causes low DPC Latency.

I noticed that unplug my USB mouse resolves USBPORT.sys's DPC Latency... I'll check my mouse driver.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 01, 2010, 02:20:16 PM
My guess whatever is causing your issue will be gone when you upgrade to Windows 7.

Who are the publishers of those files in the file properties? Are they Microsoft driver files or replaced by something else?
i have Another suspect i8042prt.sys
all drivers belong to microsoft.
I'm sure, when i upgrade to Windows 7 that will be fixed
Theory.
I think that somehow avast is forcing the drivers.
should be a combination of avast and other drivers, probably when they correct the high DPC latency in malwarebites these problems may reduce or stop.
that is why nobody can reproduce what happens to me, each computer has a specific configuration and different drivers.
NON.
I got this driver of the mouse and keyboard i8042prt.sys it is not causing high DPC latency but high ISR.
my mouse its usb end i unplug him,but not work with me.
I hope fix your problem soo.
I'll keep searching one by one, but if my theory is correct only avast can improve the system.
I think it is night in Japan,good night.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on April 01, 2010, 04:56:52 PM
i have Another suspect i8042prt.sys
all drivers belong to microsoft.
I'm sure, when you upgrade to Windows 7 that will be fixed
Theory.
I think that somehow avast is forcing the drivers.
should be a combination of avast and other drivers, probably when they correct the high DPC latency in malwarebites these problems may reduce or stop.
that is why nobody can reproduce what happens to me, each computer has a specific configuration and different drivers.
NON.
I got this driver of the mouse and keyboard i8042prt.sys it is not causing high DPC latency but high ISR.
my mouse its usb end i unplug him,but not work with me.
I hope fix your problem soo.
I'll keep searching one by one, but if my theory is correct only avast can improve the system.
I think it is night in Japan,good night.

Cako, you are much familiar with PCs than me :)

Only I found about videoprt.sys is this, maybe you already found:
With Nvidia video card, turning powermizer off would reduce DPC latency... Dynamic GPU clock change (especially clock decrease) can cause high DPC latency.

It's around noon in Brazil, right? Have a good day!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 02, 2010, 12:22:14 AM
i have Another suspect i8042prt.sys
all drivers belong to microsoft.
I'm sure, when you upgrade to Windows 7 that will be fixed
Theory.
I think that somehow avast is forcing the drivers.
should be a combination of avast and other drivers, probably when they correct the high DPC latency in malwarebites these problems may reduce or stop.
that is why nobody can reproduce what happens to me, each computer has a specific configuration and different drivers.
NON.
I got this driver of the mouse and keyboard i8042prt.sys it is not causing high DPC latency but high ISR.
my mouse its usb end i unplug him,but not work with me.
I hope fix your problem soo.
I'll keep searching one by one, but if my theory is correct only avast can improve the system.
I think it is night in Japan,good night.

Cako, you are much familiar with PCs than me :)

Only I found about videoprt.sys is this, maybe you already found:
With Nvidia video card, turning powermizer off would reduce DPC latency... Dynamic GPU clock change (especially clock decrease) can cause high DPC latency.

It's around noon in Brazil, right? Have a good day!

I know a little about computers but I learned a little more here with you and some users of the forum.
I search and I'm still researching all the drivers, and I have decided to bring this problem to a university teacher of programming here.
if I have good news I will write here again, if I have bad news I will write here too.
if you can find the solution to your problem write here.
are 12 hours of difference between Brazil and Japan, 4:00 PM here are 4:00 AM in Japan.
I hope and I will continue looking for a permanent solution to back use P2P shield.
thanks for everything.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: dajisan on April 02, 2010, 05:29:32 PM
Hello everyone! i just joined this forum because we are ALL having the SAME issue with our pcs, and we all have Avast installed :)

please read my post, i temporarily found a solution:

http://forum.avast.com/index.php?topic=56742.msg488790#msg488790

And i followed the steps here to diagnose the problem:

http://www.msfn.org/board/topic/140263-how-to-get-the-cause-of-high-cpu-usage-by-dpc-interrupt/

I hope this will serve as a bridge towards a permanent fix...
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on April 02, 2010, 06:08:18 PM
Hello everyone! i just joined this forum because we are ALL having the SAME issue with our pcs, and we all have Avast installed :)

please read my post, i temporarily found a solution:

http://forum.avast.com/index.php?topic=56742.msg488790#msg488790

And i followed the steps here to diagnose the problem:

http://www.msfn.org/board/topic/140263-how-to-get-the-cause-of-high-cpu-usage-by-dpc-interrupt/

I hope this will serve as a bridge towards a permanent fix...

dajisan, thank you for your post.

In fact, the tool you mentioned (Windows Performance Toolkit) is already tried, and unfortunately Cako is running XP on his PC... this tools run only partial on XP.
But anyway, your issue is very similar to ours, so I hope diagnosis on your PC clarify these issues. :)

Try to use Device Doctor (Device Driver updater), this may help drivers update.
http://www.devicedoctor.com/

And I also mentioned before, nVidia device driver with "powermizer" can cause high DPC Latency... it seems you use nVidia, so if you can turn it off, try and check the results.

Good luck!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 02, 2010, 06:39:36 PM
Hello everyone! i just joined this forum because we are ALL having the SAME issue with our pcs, and we all have Avast installed :)

please read my post, i temporarily found a solution:

http://forum.avast.com/index.php?topic=56742.msg488790#msg488790

And i followed the steps here to diagnose the problem:

http://www.msfn.org/board/topic/140263-how-to-get-the-cause-of-high-cpu-usage-by-dpc-interrupt/

I hope this will serve as a bridge towards a permanent fix...
Hi dajisan,welcome to the forum.
When more people report this problem, better the chance to fix it.
I could not use the Windows Performance Toolkit (which is a great tool and more precise than the one I used)
I used the rattv3 ,this it is a tool for auditing the execution times of interrupt service routines (ISRs), deferred procedure calls (DPCs)
if anyone use Windows XP can download here:
http://www.microsoft.com/whdc/DevTools/tools/RATT.mspx
go to C:\WINDOWS\system32\LogFiles\RATTV3 end open the logfile with wordpad end save to fix the words.
I also found this site that's a little more information.
http://www.microsoft.com/whdc/Driver/tips/DPC_ISR.mspx
use the tips of NON, he is very good with PCs.

NON.
I had tried your tip of PowerMizer, but I think this option exists only in mobile computers.
this configuration option does not exist here on my PC.
I use gforce 6200LE with updated drivers.
but your tip was very good, it actually causes DPC latency and should be disabled if not is being used in some PCs.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 04, 2010, 08:21:48 PM
this is unbelievable.
this happened after using the full scan by 1:39
its so difficult to fix this....... :-\.
(http://i42.tinypic.com/34oyb69.jpg)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on April 04, 2010, 08:43:41 PM
hey that super interference what happen?




happy Easter to all!!!


sign-on to avast!!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 04, 2010, 09:08:06 PM
hey that super interference what happen?




happy Easter to all!!!


sign-on to avast!!
hi my friend,this happened to me while I did a full scan, if I pause the full scan it gets low
Happy Easter!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on April 04, 2010, 09:46:46 PM
hello my friend!! did you check the service host?

i try to figure out if it is the same in mine

but see the result in mine, i will try it again if it give high peak.

friend i figure out that also give me a high peak reading if my cpu is over heat.

the cpu fan running, the electromagnetic flux it causes interference also

i don't understand the fan is mounted at the heat zinc why the EMF give interference ???

if you don't mind try to replace your processor fan a new one.

Regards!!!



Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on April 05, 2010, 01:57:35 AM
hello my friend!! did you check the service host?

i try to figure out if it is the same in mine

but see the result in mine, i will try it again if it give high peak.

friend i figure out that also give me a high peak reading if my cpu is over heat.

the cpu fan running, the electromagnetic flux it causes interference also

i don't understand the fan is mounted at the heat zinc why the EMF give interference ???

if you don't mind try to replace your processor fan a new one.

Regards!!!
:o

I found some articles saying cleaning PC's cooling system (CPU Fan, heatsink, vent...) solves high DPC Latency, so it's worthy to try it.

If CPU got over heat, CPU downs its clock to protect itself, and this causes performance decline... so normally DPCs don't consume much CPU time, but with low CPU performance it consumes much CPU time.
I've forgotten Cako runs his PC all day (moreover with full scan!), so it's very likely to happen this symptom... what a fool I am! :-X :'(

Anyway, Happy Easter to all! If your problem is solved, it must be a present from the sky. ;)

Edit:
I have some red bars... now I run my PC with Battery-mode (CPU clock downs to 800MHz).

Edit2:
I now remember this problem doesn't appear with .396... so it seems this is not the reason. :P
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 06, 2010, 01:33:38 AM
hi guys.
thanks for the tip,
but on my PC when the processor becomes very hot it restarts my pc.
To  fix it i just clean the fan and the problem is fixed.
I check the fan and the processor end its clean end working properly here.
I think NON is right.
fix this problem must be a present from the sky.
but I'll keep trying.
so far I dont have much news.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 10, 2010, 10:16:08 PM
fixed problem with the mouse.
I uninstall a PC game called SWAT 4 to fix it.
and i cleaned the windows registry.
the mouse stopped jumping from the one side to other side on the screen.
I think somehow avast and the game had a conflict because when I disable all the shields from avast also stopped the problem.

DPC latency is not fixed yet.
I updated to version eMule 0.50a end the problem continues.
I'll wait for the next version of avast free (final), I will update and expect some results.
but I dont have hope in the next version of avast
i dont think this will go help end alleviate the problem.
I hope I'm wrong.
I will keep trying find the solution to be able to use the P2P shield again .. ;)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on April 11, 2010, 03:53:29 AM
fixed problem with the mouse.
I uninstall a PC game called SWAT 4 to fix it.
and i cleaned the windows registry.
the mouse stopped jumping from the one side to other side on the screen.
I think somehow avast and the game had a conflict because when I disable all the shields from avast also stopped the problem.

Hi Cako,
I'm glad to hear one of your problems were fixed. I hope you are not too tired.

Quote
DPC latency is not fixed yet.
I updated to version eMule 0.50a end the problem continues.
I'll wait for the next version of avast free (final), I will update and expect some results.
but I dont have hope in the next version of avast
i dont think this will go help end alleviate the problem.
I hope I'm wrong.
I keep trying to find the solution to be able to use the P2P shield .. ;)

Latest build contains some fixes about winsock, which is related to network. I hope this has some effects on your problem.
But, I feel that the circumstances of your problem is now changing... before you posted an terrible DPC Latency after full-scan. Full-scan is not related to P2P shield, so it seems the culprit is not network-related but another stuff.

I'll suggest these. I don't know whether you already did these or not, but just in case:
- Does disabling avast heuristic in P2P shield change your issue?
- Hard HDD access with/without avast show some changes? (related to full-scan issue)
- Try to clean unused / remained security-software device driver.
Device manager -> "Show" menu? -> Enable "Show unshowed device"? -> Un Plug & Play driver
I think there are many remains in this category, so delete them. Please be careful not to delete system driver (driver vender's name will help distinction).
Sorry for "?" marks... I don't know how these menus called in English :-X


And here is my situation:
Update graphic driver: No major effect
Install vendor's mouse driver/utility: Module "USBPORT.sys" disappear and "Unknown" appear in xperf ???
Uncheck "increase mouse accuracy": A bit decline DPC Latency caused by USBPORT.sys :)
Change audio codec (Windows default -> ffdshow Audio Codec): Sound shuttering decreases dramatically :o
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 11, 2010, 06:06:32 PM
fixed problem with the mouse.
I uninstall a PC game called SWAT 4 to fix it.
and i cleaned the windows registry.
the mouse stopped jumping from the one side to other side on the screen.
I think somehow avast and the game had a conflict because when I disable all the shields from avast also stopped the problem.

Hi Cako,
I'm glad to hear one of your problems were fixed. I hope you are not too tired.

Quote
DPC latency is not fixed yet.
I updated to version eMule 0.50a end the problem continues.
I'll wait for the next version of avast free (final), I will update and expect some results.
but I dont have hope in the next version of avast
i dont think this will go help end alleviate the problem.
I hope I'm wrong.
I keep trying to find the solution to be able to use the P2P shield .. ;)

Latest build contains some fixes about winsock, which is related to network. I hope this has some effects on your problem.
But, I feel that the circumstances of your problem is now changing... before you posted an terrible DPC Latency after full-scan. Full-scan is not related to P2P shield, so it seems the culprit is not network-related but another stuff.

I'll suggest these. I don't know whether you already did these or not, but just in case:
- Does disabling avast heuristic in P2P shield change your issue?
- Hard HDD access with/without avast show some changes? (related to full-scan issue)
- Try to clean unused / remained security-software device driver.
Device manager -> "Show" menu? -> Enable "Show unshowed device"? -> Un Plug & Play driver
I think there are many remains in this category, so delete them. Please be careful not to delete system driver (driver vender's name will help distinction).
Sorry for "?" marks... I don't know how these menus called in English :-X


And here is my situation:
Update graphic driver: No major effect
Install vendor's mouse driver/utility: Module "USBPORT.sys" disappear and "Unknown" appear in xperf ???
Uncheck "increase mouse accuracy": A bit decline DPC Latency caused by USBPORT.sys :)
Change audio codec (Windows default -> ffdshow Audio Codec): Sound shuttering decreases dramatically :o

Hi NON  ;D
my english is not very good, but I think it was possible to understand,your problem is almost solved,I think.
I am very happy to know. ;D ;D
Quote
- Does disabling avast heuristic in P2P shield change your issue?
I had already done it, the problem it only happens when files are scanned emule.

Quote
- Hard HDD access with/without avast show some changes? (related to full-scan issue)
- Try to clean unused / remained security-software device driver.
Device manager -> "Show" menu? -> Enable "Show unshowed device"? -> Un Plug & Play driver
I think there are many remains in this category, so delete them. Please be careful not to delete system driver (driver vender's name will help distinction).
Sorry for "?" marks... I don't know how these menus called in English
I dont did this,but i will.
I will put the result later.
thanks.....
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 11, 2010, 06:14:54 PM
I will install the 499 version right now, but I think it should not change much ..
I will install and test...... :-\
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Moba on April 11, 2010, 06:30:48 PM
I can confirm the issue after running the DPC tool on my X60 Thinkpad with Windows 7 Ultimate (32 bit). Removing Avast solved the issue.

However, "destroy Avast's reputation" might be a bit harsh; I'm sure the Avast team will look in to it. Lots of software have bugs and with all the hardware/software combinations possible, it's impossible for any dev team to produce 100% bug free software.

Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Vlk on April 11, 2010, 06:42:26 PM
I can confirm the issue after running the DPC tool on my X60 Thinkpad with Windows 7 Ultimate (32 bit). Removing Avast solved the issue.

However, "destroy Avast's reputation" might be a bit harsh; I'm sure the Avast team will look in to it. Lots of software have bugs and with all the hardware/software combinations possible, it's impossible for any dev team to produce 100% bug free software.

The point of this lengthy thread (or our contributions so far) is that we have been "looking into" this issue for like half a year now. The problem is not reproducible on our test systems, which makes me think it has to be a conflict with another program / driver.

However, about half of our test systems exhibits the behavior no matter if avast is installed or not - just a clean install of Windows plus all hardware drivers are enough to have DPC latencies go haywire every now and than.

Performance tuning is something we spend significant time on; the DPC latency problem, however, is so subtle and influenced by so many external factors that it really needs to be analyzed on individual basis, case by case. This is also why the extensive documentation accompanying the DPC test tool doesn't tell you how to solve the problem - there's no simple here.


Now, if the problem is reproducible on your system (win7), it would be useful if you could do the xperf.exe experiment for us, as described above. Is that something you could do?

Thanks,
Vlk
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 11, 2010, 07:59:53 PM
I am conscious of the difficulty to fix this problem with the DPC latency.
I spent many hours researching and trying to do tests on my PC to fix this.
but I never heard about DPC latency before installing avast 5.
anyway, i dont spend my time, knowledge about anything is very good.
I am not a developer, I dont know how to programming a software, but I am persistent.
I dont know much about PHP but when I needed, learn and create my own PHP mail.
I'm not very smart if I can anyone can.
but drivers are not PHP, and in my country it is illegal to modify software without authorization.
I dont want trouble with the law.
I can not install the WDK end modify the drivers one by one.
so I just do what I can do.
look:
AVAST free 5.0.499 after 40 minutes using P2P shield to scan emule files,no DPC problems:
(http://i40.tinypic.com/33pec09.jpg)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on April 12, 2010, 02:45:57 PM
Hi Cako,

Hi NON  ;D
my english is not very good, but I think it was possible to understand,your problem is almost solved,I think.
I am very happy to know. ;D ;D

Changing audio codec is only an allopathy, not a permanent solution... but I don't have any complaint with this anyway. :)
Now I think my (relatively high ::)) DPC Latency is caused by Comodo Firewall... they had same issue before, and it can happen on my PC too.


And Mova, welcome to the forums. If you have some time to analysis your DPC issue, please do it; it can help identify what happens on your / our PCs.
Here is usage of xperf again:
Edit: You can download Windows Performance Analysis Toolkit from next post by vlk.

Quote
To try and help identify the cause of this phenomena, perhaps you would care to delve a little deeper into your systems. The DPC latency checker, whilst being a helpfulutility, sadly lacks any useful information. To get more detailed information, please use the following guide and report your findings:

2. Download Windows Symbols Package for your OS (you may or may not need them) http://www.microsoft.com/whdc/devtools/debugging/symbolpkg.mspx#d

3. Install the Windows Performance Analysis Tools (you might wish to change the install path to something easy to navigate to)

4. Open a command prompt (elevated if necessary) and navigate to the xperf folder the default is "C:\Program Files\Microsoft Windows Performance Toolkit"

5. For the sake of simplicity type:

 xperf -on DiagEasy and press return.

This will begin the trace. I suggest letting it run for several minutes to ensure you capture the details required.

6. After a time has passed type :

xperf -d trace.etl and press return.

This will stop the trace.

7. Type:

xperf trace.etl and press return.

This will display the results. We could have collected more specific data but using the DiagEasy switch is good enough for our purposes.

8. Scroll down to the section headed DPC CPU Usage.

9. Select a nice big spike, this corresponds to the spikes you will have observed in DPC latency checker. Select the spike and right click. From the menu select Summary Table. This will open a new window with details regarding drivers. The higher the value the more problematical the driver.

10. Report your findings here.

Best wishes,
NON
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Vlk on April 12, 2010, 03:00:50 PM
BTW the Windows Performance Analysis Tools can easily downloaded from here:
32-bit http://public.avast.com/~vlk/wpt/wpt_x86.msi
64-bit: http://public.avast.com/~vlk/wpt/wpt_x64.msi

Getting them via the SDK is a pain.

Thanks
Vlk
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on April 12, 2010, 03:47:43 PM
BTW the Windows Performance Analysis Tools can easily downloaded from here:
32-bit http://public.avast.com/~vlk/wpt/wpt_x86.msi
64-bit: http://public.avast.com/~vlk/wpt/wpt_x64.msi

Getting them via the SDK is a pain.
:o 8)

Many thanks, vlk 8)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: snarky on April 12, 2010, 05:19:48 PM
I installed AIS 5.0.462 yesterday.  I'm also using uTorrent 2.0 and WinXP Pro SP3 (32-bit).

I have noticed higher-than-usual DPC usage on my system.  I run Process Explorer constantly in the tray, and at any given time, DPC is using 15-30%.  I know for certain that this is not typical for my system, since I have always checked Process Explorer very frequently.

So far, there has been one time (that I've noticed, at least) that DPC usage was 80-100%.

I do have uTorrent checked in the P2P shield.  I know it's not checked by default.  I was experimenting.

When I stop the P2P shield, the DPC usage remains 15-30% continually.  I have not tried disabling the P2P shield and rebooting.

I'll probably simply disable and/or remove the P2P shield and hope that fixes the problem.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 12, 2010, 05:57:06 PM
I installed AIS 5.0.462 yesterday.  I'm also using uTorrent 2.0 and WinXP Pro SP3 (32-bit).

I have noticed higher-than-usual DPC usage on my system.  I run Process Explorer constantly in the tray, and at any given time, DPC is using 15-30%.  I know for certain that this is not typical for my system, since I have always checked Process Explorer very frequently.

So far, there has been one time (that I've noticed, at least) that DPC usage was 80-100%.

I do have uTorrent checked in the P2P shield.  I know it's not checked by default.  I was experimenting.

When I stop the P2P shield, the DPC usage remains 15-30% continually.  I have not tried disabling the P2P shield and rebooting.

I'll probably simply disable and/or remove the P2P shield and hope that fixes the problem.

if you want a temporary solution uncheck the utorrent in the P2P shield's option.
but before doing that use the Windows Performance Analysis Tools if you use the windows vista/7 .
You can download here (links from vlk) :
32-bit http://public.avast.com/~vlk/wpt/wpt_x86.msi
64-bit: http://public.avast.com/~vlk/wpt/wpt_x64.msi


if you use the windows XP use the rattv3 ,this it is a tool for auditing the execution times of interrupt service routines (ISRs), deferred procedure calls  (DPCs)
You can download here:
http://www.microsoft.com/whdc/DevTools/tools/RATT.mspx

go to C:\WINDOWS\system32\LogFiles\RATTV3 end open the logfile with wordpad end save to fix the words.
Put the log here.

Quote
Changing audio codec is only an allopathy, not a permanent solution... but I don't have any complaint with this anyway. Smiley
Now I think my (relatively high Roll Eyes) DPC Latency is caused by Comodo Firewall... they had same issue before, and it can happen on my PC too.
NON, we will continue to search for a permanent solution. :D

look:
AVAST free 5.0.499 after 4:29 minutes using P2P shield to scan emule files,the DPC problems again:
well, if they cant simulate this problem, they cant fix.. :'(
(http://i42.tinypic.com/jsd7yb.jpg)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: PapaSmurf on April 12, 2010, 06:41:21 PM
Hello,
Just an average user here, so I tried to duplicate system slow down and was unable to do so.
The image shows a few things going on at one time, and I have not noticed any slow down.
But I do thank you for this topic. It has allowed me to test for things that I might not have tested for.




(http://i40.tinypic.com/ae2zxg.jpg)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: snarky on April 12, 2010, 07:12:18 PM
if you use the windows XP use the rattv3 ,this it is a tool for auditing the execution times of interrupt service routines (ISRs), deferred procedure calls  (DPCs)
You can download here:
http://www.microsoft.com/whdc/DevTools/tools/RATT.mspx

go to C:\WINDOWS\system32\LogFiles\RATTV3 end open the logfile with wordpad end save to fix the words.
Put the log here.

I installed RATTV3.  Now I have 3 relatively large log files.  Not knowing what's in them, and not being able to really read them, I'm not posting them anywhere.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 12, 2010, 07:23:45 PM
if you use the windows XP use the rattv3 ,this it is a tool for auditing the execution times of interrupt service routines (ISRs), deferred procedure calls  (DPCs)
You can download here:
http://www.microsoft.com/whdc/DevTools/tools/RATT.mspx

go to C:\WINDOWS\system32\LogFiles\RATTV3 end open the logfile with wordpad end save to fix the words.
Put the log here.

I installed RATTV3.  Now I have 3 relatively large log files.  Not knowing what's in them, and not being able to really read them, I'm not posting them anywhere.
wait a few minutes and the file will transform into .txt file (notepad).
or stop rattv3 using the icon (try icon).
upload your file here.
http://uploading.com/ end put the link here.
(http://i42.tinypic.com/vfecgi.jpg)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: snarky on April 12, 2010, 07:27:43 PM
OK thanks.  Here's the file.  I'm not 100% sure I didn't screw it up by disabling the P2P shield before closing RATTV3, but I can't devote much energy to this.  The whole reason I am trying avast is because another vendor's product was consuming too much of my time...
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 12, 2010, 08:55:02 PM
OK thanks.  Here's the file.  I'm not 100% sure I didn't screw it up by disabling the P2P shield before closing RATTV3, but I can't devote much energy to this.  The whole reason I am trying avast is because another vendor's product was consuming too much of my time...

well my friend, I looked at your log and I have several drivers that you have.
and are even with high ISR and DPC.
VIDEOPRT.SYS
ntoskrnl.exe
Ndis.sys

but how avast is in conflict with them is a mystery.

NON.
I did the test that you suggested and had no results, still the same thing if I leave the P2P shield scans  emule files,but thanks again. :)

fear
this only happens to me when I use the P2P shield, if I upgrade to win7 and stick with high DPC without even using emule!
probably I'll  upgrade next year...
I'm afraid of it.................

PapaSmurf
DPC latency cause sound problems, no slow the computer,(in my case,until now)
in your photo shows green peaks, but went through a red  peaks and you did not show.
the DPC shows in your photo 18925us , read the warning about  Driver Error message "some device drivers on this machine"
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Chris Thomas on April 12, 2010, 09:15:20 PM
Oh My God

I am also having DPC Latency problem with one of my PC

Check this screenshot

(http://i41.tinypic.com/14nz983.jpg)

How do I fix this?

Edited:

Only when using YouTube
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on April 13, 2010, 01:45:41 AM
Oh My God

I am also having DPC Latency problem with one of my PC

Check this screenshot

(http://i41.tinypic.com/14nz983.jpg)

How do I fix this?

Edited:

Only when using YouTube
:o

I can see you use Vista/7 PC, so please install Windows Performance Analysis Toolkit ,run xperf and see results.
With Stack walking method, you can see what function of the driver causes this DPC Latency.

1. Add the following environment variable:

_NT_SYMBOL_PATH = srv*C:\SrvSymbols*http://msdl.microsoft.com/download/symbols

2. From a command prompt, navigate to the Xperf directory and type

xperf -on Latency –stackwalk Profile

3. Wait for the high DPC activity to occur

4. type this and analysis will stop

xperf -d stackwalk.etl

5. Then run this command:

xperf stackwalk.etl

6. After opening xperfview window, go to "Trace" menu and check "Load symbols". If License certification window appear, press "Yes" and wait a minute.

7. Go to the area [DPC CPU Usage] and select high peak, then right click and press [Summary Table] on context menu.

8. Click selector tab (left in window), open [Column Chooser] and check Function at least.

9. You can see what function causes high DPC Latency in "Function" column.

10. Please report your findings here. Drivers' name, function, or any other findings.

Sorry for my bad English, I brought this way from Japanese WDK Support blog and I don't have enough skills to translate whole article. :-X

Best wishes
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 13, 2010, 02:23:35 AM
Oh My God

I am also having DPC Latency problem with one of my PC

Check this screenshot

How do I fix this?

Edited:

Only when using YouTube

good morning or good evening everyone.

Chris Thomas.
Welcome.
follow the tips of NON.
put your log file (or your screenshot) here using the xperf, may help the ALWIL to see which drivers are being affected.
By coincidence some of them are the same to me,snarky end NON.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on April 13, 2010, 02:44:10 PM
Quote
in your photo shows green peaks, but went through a red  peaks and you did not show.
the DPC shows in your photo 18925us , read the warning about  Driver Error message "some device drivers on this machine"

wow! you are an expert now in dpc.

that only one peak come from the noise of network :D

if you can monitor the db of network, you can see that peak interphase with that noise :D

that 1 also in my peak rating :D

looks like cako and NON are best team in this post :D

Regards!!!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 13, 2010, 03:48:10 PM
Quote
in your photo shows green peaks, but went through a red  peaks and you did not show.
the DPC shows in your photo 18925us , read the warning about  Driver Error message "some device drivers on this machine"

wow! you are an expert now in dpc.

that only one peak come from the noise of network :D

if you can monitor the db of network, you can see that peak interphase with that noise :D

that 1 also in my peak rating :D

looks like cako and NON are best team in this post :D

Regards!!!

just 1 red peak end the sound problem will appear on my PC happens every red peak.
he mistook slow pc with this problem and I just tell to him.
I'm no a expert and i dont like sarcasm. >:(
Do you have done some research or something more useful to help solve this problem  ???
thanks for help us finding a solution  ;D
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on April 13, 2010, 05:49:08 PM
Quote
Do you have done some research or something more useful to help solve this problem

i did, but run out of solution.
what can i do? that battery control no updated software ;D

look, if i disable it no peak, but if enable the peak is about 3209 micro second

and some dpc peak is created by wireless card, just like the peak of chris :D

Best Regards!!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on April 13, 2010, 05:52:53 PM
opps to big this the next picture when enable
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on April 13, 2010, 06:01:24 PM
another picture :D
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on April 13, 2010, 06:04:08 PM
continue from 3rd picture
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on April 13, 2010, 06:31:54 PM
bong2x, you already find what causes your problem. :D

Try to use Device Doctor, it will show you more updates than MicrosoftUpdate. I don't think it could provide ACPI driver update, but may provide Wireless-Lan adapter drivers.
And, I heard BIOS (on mother-board) has something to do with ACPI before. So if you have BIOS Update on your computer, it's worth a try.
http://www.devicedoctor.com/


It seems your DPC Latency is also caused by power-management system... dynamic CPU clock changing, like nVidia Video Card?
I tired this but I don't have any change except for disappearing taskbar icon ::). Anyway, thanks for the information.

@Chris Thomas:
I also tried to see videos on YouTube ;D, but I don't realize any changes so far. Very environment-dependence issue. :-\
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on April 13, 2010, 06:51:43 PM
ok! thanks NON,

i am looking for ACPI but i cannot find it. its part of OS but its only Optional if you use it or not.

cannot find also the good driver for wireless card. just disable it. its not important no wifi here ;D

By The Way(btw) i will try your recommended software, and i will post here if there is development ;)

i do not have video card only in motherboard,


Best Regards!!!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 13, 2010, 07:07:15 PM
continue from 3rd picture
Congratulations bong2x, you did a great job.
this problem is too complex, for some people just update drivers end this will be fixed for other just uninstalled.
for others,its clear,asvast is in conflict with one or more drivers.
just uninstall or stop using some resources from avast will stop the problem, so it is very important to know which drivers are causing the problem to be closer of a solution.
in your case you found what is the cause of your problem, this is very good. ;D ;D
everything you put here on this topic will help others with the same problem.thanks..
this problem is very stressful,I'm sorry if I offended anyone... :-\
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Dwarden on April 13, 2010, 07:26:48 PM
the DPC latency problem is indeed very complex issue

often it's driver (mainly hardware related one like drive controllers, NIC (very often wificards), audiocards or USB devices) usually bad coding
then it's collision of drivers either for hardware or also software again usually bad coding

and then there are very hidden DPC issues related to mainboard BIOS/firmware of certain controllers
(in this case You need contact Your mainboard manufacturer if You sure about it,
but usually it's no chance to discover unless one bios version all was ok and next one DPC went crazy)

ofcourse it can be also combination of above factors which makes it pain to follow even while using
Rattv3, Kernrates, KRView or Xperf ...

yet in this case it's easiest on W7 to trace than previous OSes
ofcourse this not apply for hardware related issues
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on April 14, 2010, 12:18:20 AM
no luck NON. :'(

i have already the latest driver of my wireless card :'(


thanks!

Best Regards!!!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: snarky on April 14, 2010, 03:18:52 AM
I removed avast! Internet Security and installed avast! Free, and did not install the P2P shield at all this time.

No DPC issues at all anymore.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Vlk on April 14, 2010, 07:23:27 AM
I removed avast! Internet Security and installed avast! Free, and did not install the P2P shield at all this time.

No DPC issues at all anymore.

Wait for a few hours/day and check again. It's usually worse when the system is up for some time.
I still refuse to admit that the issue is P2P Shield related (unless it's scanning excessive number of files, which can be easily verified using the
P2P Shield's realtime traffic chart) - firewall, maybe, but not P2P Shield.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on April 14, 2010, 11:02:12 AM
snarky,

the p2p shield is very important to me and to all user that like to download music, video or live coverage.

 the dpc is not connected with my p2p but dpc peak is generated in my system when: there is an interruption in power (battery Driver) or electromagnetic wave signal that is modulated by wireless card. i did try to monitor the wifi noise the peak of dpc is interphase with it.

and the visualization alchemy random increase the peak also but it is small amount only.

Regards!!!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on April 14, 2010, 11:20:58 AM
and this is my p2p  shield sensitivity settings
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 14, 2010, 03:01:36 PM
I removed avast! Internet Security and installed avast! Free, and did not install the P2P shield at all this time.

No DPC issues at all anymore.

hi snarky!
you have exactly the same problem I have.
when I disable the programs (limewire,emule end utorrent) in the advanced settings or disable the P2P shield my DPC latency its normal ever.
see this picture, my PC its turned on about 16 hours without DPC problems .
I'm now using avast free version 5.0.504 without P2P shield scan
This is my temporary solution.
snarky, leave your PC switched on for 15 or 24 hours and put a picture like that here if you can, thanks.
(http://i42.tinypic.com/os5on5.jpg)

this happens after the P2P shield scans files of emule for hours.
But they refuse to believe, is not about to admit, but to believe and find a solution
many people must have the same problem and dont know ..
My conf.
(http://i44.tinypic.com/35hhgma.jpg)

(http://i43.tinypic.com/25z1ji8.jpg)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: snarky on April 14, 2010, 10:47:30 PM
Wait for a few hours/day and check again. It's usually worse when the system is up for some time.
I still refuse to admit that the issue is P2P Shield related (unless it's scanning excessive number of files, which can be easily verified using the P2P Shield's realtime traffic chart) - firewall, maybe, but not P2P Shield.

Still no noticeable DPC CPU usage.

But you very well may be right.  Now that I'm using the free product, I obviously don't have the firewall installed.  This would also explain why (when I still had IS installed) DPCs kept using lots of CPU time even after P2P shield was disabled.  I'm not really that interested anymore though, to be honest.

the p2p shield is very important to me and to all user that like to download music, video or live coverage.

It's important to me too, but after all these years, P2P shield still doesn't work well with uTorrent (i.e. uTorrent is deselected by default), and uTorrent is the only P2P client I use, so even if there is no DPC issue with it, why would I use the P2P shield?
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 16, 2010, 03:11:34 AM
very strange.
I used process explorer on my PC and am trying see what causes the high DPC.
on properties I've seen it in the photo.
I dont know if it is a process or a driver.
I'm sure,when it gets in this position the peak appears red in my DPC latency checker.
It seems the problem happens when the avast ends the scan and not during the scan.
when I'm using P2P shield to scan files emule.(keep testing and looking)
using free avast 5.0.507.
(http://i42.tinypic.com/25iaro1.jpg)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 16, 2010, 07:43:04 PM
Good news. :D
after doing the full scan on my system by 1:43 (an hour and forty-three minutes) i dont have any problem of slow down or high DPC on my computer.
look at the difference between this photos.

this happened after use the full scan by 1:39 using avast free 5.0.462

(http://i42.tinypic.com/34oyb69.jpg)


this happened after use the full scan by 1:43 using avast free 5.0.507
this is a huge difference.
I tested it twice and I think the latest changes in avast fix this problem on my pc.

(http://i42.tinypic.com/taqws5.jpg)

but unfortunately when I test  the P2P shield when he scanned using only the P2P shield, still appear red peaks and sound problems.
but the free version of avast 5.0.507 is much more stable and faster on my system.

(http://i42.tinypic.com/2lafndf.jpg)

EDIT- time edited 1:40 to 1:43 (the real time) - sorry my mistake
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on April 16, 2010, 08:12:27 PM
something like distortion. ::)

looks like the same peak as battery controller enable,

 ::) is p2p shield use impulsive amount of power when it is scanning?  ???

Regards!!!


Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on April 16, 2010, 08:18:00 PM
(http://i42.tinypic.com/taqws5.jpg)

More stable than mine. ;D ;D ;D  Good news. 8) I'm glad to hear that.
(say, it doesn't mean my PC is unstable ;)).

What do eMule's properties in Process Explorer show when red peak appears? It may be useful to identify what happened.


something like distortion. ::)

looks like the same peak as battery controller enable,

 ::) is p2p shield use impulsive amount of power when it is scanning?  ???

Regards!!!

Scanning many files can cause high CPU (and HDD) usage, so disable power-controller device (Desktop PC also has it, maybe) is worth trying, I think.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: bong2x on April 16, 2010, 08:49:10 PM
Quote
Scanning many files can cause high CPU (and HDD) usage, so disable power-controller device (Desktop PC also has it, maybe) is worth trying, I think.

i like this line NON :D

if something useless, then disable it or uninstall it.

i think maybe by the time i install my os its ask me if i want to install battery controller, i did put in yes and continue anyway :D
but i don't have battery mounted in the computer ;D
so what this driver do? when it is enable?

Thanks!!!

Best Regards!!!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 17, 2010, 03:42:26 PM
something like distortion. ::)

looks like the same peak as battery controller enable,

 ::) is p2p shield use impulsive amount of power when it is scanning?  ???

Regards!!!


hi bong2x,I do not know if it's a distortion, but may be something related to a too small page file or where the page file could dynamically grow (start- end and size not set to the same value) with memory which avast administers. (probably  ::) )

NON.
hi. :)
I am very happy to do the full scan without slow down my computer or have high DPC,Congratulations ALWIL  :)
sorry for replying late,I took this picture at the exact moment when I had a red peak.

(http://i42.tinypic.com/r7om6d.jpg)

I'm trying to use the Process Explorer to help positively identified in real time what process or driver is causing it all.
I would use the P2P shield again.
so,i find this.
Download Process Explorer,dont need install,just use.
http://technet.microsoft.com/en-us/sysinternals/bb896653.aspx
Download Debugging Tools for Windows.
http://www.microsoft.com/whdc/devtools/debugging/installx86.Mspx#EQB

Go to Process Explorer's Options/Configure Symbols, and in the Dbghelp.dll path box enter the new path to DBGHELP.DLL,C:\Program Files\Debugging Tools for Windows\dbghelp.dll
In the Symbols path box, enter srv*C:\Symbols*http://msdl.microsoft.com/download/symbols
for symbol resolution to work, you must change the "Dbghelp.dll path" to point at the copy of dbghelp.dll that was installed with the Debugging Tools for Windows.
(I dont have done that part, I'm kinda busy.)

vlk and (or) ALWIL team.
Probably I dont have enough knowledge to solve it myself, I just can do its try to send as much of the Information for ALWIL try to find a solution.
I know about the difficulty of it, but I want my P2P shield working again.
Its not just for me, I always help when I can,look:
http://br.answers.yahoo.com/dir/index;_ylt=AtsyD6j4zSpgdW8tLXXR50vHwIlQ;_ylv=3?sid=396545660
Here, the right of the screen I am leader of category computers and internet of yahoo answers in Brazil.
only one hour per day I became leader, that's nothing, but it shows my intention to help.
this problem with DPC is the same as happened with the web shield, but I know,if the problem cant be simulated ALWIL has no way to correct, but believe me and try to verify the information that I gave,and i will still I giving.

After nearly 3 months
slow mouse jumping on the screen - FIXED (after I uninstall the game swat 4)
high DPC in the full scan - FIXED - (after ALWL provide fixes in avast free  5.0.507)
high DPC problem while using the P2P shield - NOT FIXED - (who will fix it  ??? )

If I dont find a solution to fix it, at least i will improve my English a little. ;D

Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: avvidro on April 17, 2010, 10:26:24 PM
Oi Cako,  como vai?

A primeira e mais urgente coisa para melhorar seu inglês é que End é fim e não E (&). Em inglês, E é And.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 17, 2010, 10:52:28 PM
Oi Cako,  como vai?

A primeira e mais urgente coisa para melhorar seu inglês é que End é fim e não E (&). Em inglês, E é And.


ola avvidro !
valeu !! eu sempre esqueço,eu não estou acustumado em escrever em inglês  ;D
hi avvidro !
thanks !! I always forget, I'm not very accustomed to write in English  ;D
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on April 18, 2010, 04:06:28 AM
I'm trying to use the Process Explorer to help positively identified in real time what process or driver is causing it all.
I would use the P2P shield again.
so,i find this.
Download Process Explorer,dont need install,just use.
http://technet.microsoft.com/en-us/sysinternals/bb896653.aspx
Download Debugging Tools for Windows.
http://www.microsoft.com/whdc/devtools/debugging/installx86.Mspx#EQB

Go to Process Explorer's Options/Configure Symbols, and in the Dbghelp.dll path box enter the new path to DBGHELP.DLL,C:\Program Files\Debugging Tools for Windows\dbghelp.dll
In the Symbols path box, enter srv*C:\Symbols*http://msdl.microsoft.com/download/symbols
for symbol resolution to work, you must change the "Dbghelp.dll path" to point at the copy of dbghelp.dll that was installed with the Debugging Tools for Windows.
(I dont have done that part, I'm kinda busy.)

I'll try this. Thanks for the tips.

Quote
http://br.answers.yahoo.com/dir/index;_ylt=AtsyD6j4zSpgdW8tLXXR50vHwIlQ;_ylv=3?sid=396545660
Here, the right of the screen I am leader of category computers and internet of yahoo answers in Brazil.
only one hour per day I became leader, that's nothing, but it shows my intention to help.

Wow, you are the top of the leaders, great. 8)
I'm also one of answerer in Yahoo answers in Japan (especially computers too), but I have never got the top. I'm a minor one. ;D

I'll test with Process Explorer when sound chattering occurs.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: avvidro on April 19, 2010, 03:52:40 AM
After nearly 3 months
slow mouse jumping on the screen - FIXED (after I uninstall the game swat 4)
high DPC in the full scan - FIXED - (after ALWL provide fixes in avast free  5.0.507)
high DPC problem while using the P2P shield - NOT FIXED - (who will fix it  ??? )
At other hand, it is not cool the way Support team seems to be "slipping" away from the core of this issue. Well, since the DPC problem is not occurring with everybody, the team can "push it with the belly". Well, one or other way we don't have entire certainty, but you, you could contact the secunia (ponto) com site. If they notice and publish, the approach of the problem will be very different. Indeed it will. At another hand we should take it easy with the people here, since many users post here putting guilt of every their problem to Avast.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: coolsilver on April 19, 2010, 04:46:27 AM
If you can't replicate it, can't find it in code you the developer controls, or just don't know how or why it happens sometimes....


You can't fix it. They haven't slipped, dodged or ignored the issue. You notice people had issues with a DVD player driver and other programs they could determine. Those were fixed quickly and would be the same if they knew why.

It's sad they have to add an additional 50k of code to work around other programs flaws. I'm sure they had to do some fancy patch work for the multiple versions of Windows.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on April 19, 2010, 05:03:50 AM
After nearly 3 months
slow mouse jumping on the screen - FIXED (after I uninstall the game swat 4)
high DPC in the full scan - FIXED - (after ALWL provide fixes in avast free  5.0.507)
high DPC problem while using the P2P shield - NOT FIXED - (who will fix it  ??? )
At other hand, it is not cool the way Support team seems to be "slipping" away from the core of this issue. Well, since the DPC problem is not occurring with everybody, the team can "push it with the belly". Well, one or other way we don't have entire certainty, but you, you could contact the secunia (ponto) com site. If they notice and publish, the approach of the problem will be very different. Indeed it will. At another hand we should take it easy with the people here, since many users post here putting guilt of every their problem to Avast.

Hi avvidro.
I'll follow your tip.
this happened after the 396 version,but now some problems have been resolved I think it's just a matter of time to fix it permanently.
I did not know what was DPC latency, only after much research I could find it.
I keep searching and using many programs to find a solution,a few people have the same problem.
do this without knowledge of the Construction of drivers and software its very painful and takes a lot of my free time.

Quote
At another hand we should take it easy with the people here, since many users post here putting guilt of every their problem to Avast.
you have reason, I dont want be confused with these people, so I'm doing everything possible to positively identified with 100% certainty what drivers or programs are doing it on my P2P shield.
Its very painful and disappoint, sometimes I dont know what to look for.
thanks again,you seem to be a conscious person when writing. :)

NON.
Quote
Wow, you are the top of the leaders, great.
I'm also one of answerer in Yahoo answers in Japan (especially computers too), but I have never got the top. I'm a minor one.
I'll test with Process Explorer when sound chattering occurs.
thanks NON,You're a great guy.
may be you are not in the top on Yahoo answers, but you are the first here,thanks again  ;D
I install the Debugging Tools for Windows and I'm researching and I will try to use it to debug a file.
I also want to see if it is possible to debug drivers and dll,without risk to my computer,I found some tutorials about Debugging Tools, I will study them and try.. :o

bong2x
Quote
i like this line NON Cheesy

if something useless, then disable it or uninstall it.

i think maybe by the time i install my os its ask me if i want to install battery controller, i did put in yes and continue anyway
but i don't have battery mounted in the computer
so what this driver do? when it is enable?

Thanks!!!

Best Regards!!!

Hi bong2x.
try disabling this using the manages services.
I tried to research something about it and found nothing significant.
sorry. :'( :'(

coolsilver
Quote
If you can't replicate it, can't find it in code you the developer controls, or just don't know how or why it happens sometimes....
You can't fix it. They haven't slipped, dodged or ignored the issue. You notice people had issues with a DVD player driver and other programs they could determine. Those were fixed quickly and would be the same if they knew why.
It's sad they have to add an additional 50k of code to work around other programs flaws. I'm sure they had to do some fancy patch work for the multiple versions of Windows.

hi.
Quote
You can't fix it.
I know I cant fix alone or myself, but I can try,and give information if possible for this to be resolved.
it is very difficult,especially for me, but I have the intend to insist a little more.
Thank you.

EDITED- i will make this myself.......(about debug,i hope dont damege my PC)
Debugging Tools for Windows 62 bit and 32 bit
http://www.microsoft.com/whdc/devtools/debugging/default.mspx
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: NON on April 19, 2010, 05:14:47 PM
Hi Cako,

Quote
thanks NON,You're a great guy.
may be you are not in the top on Yahoo answers, but you are the first here,thanks again 
I install the Debugging Tools for Windows and I'm researching and I will try to use it to debug a file.
I also want to see if it is possible to debug drivers and dll,without risk to my computer,I found some tutorials about Debugging Tools, I will study them and try..
Thanks much, I respect your knowledge and efforts. Praise is yours, of course, not mine ;)
Unfortunately I don't have enough time to analysis this deeply now, but I'll try it at no distance date.

Quote
EDITED- i will make this myself.......(about debug,i hope dont damege my PC)
Debugging Tools for Windows 62 bit and 32 bit
http://www.microsoft.com/whdc/devtools/debugging/default.mspx

Maybe there is no need to say this to you (you're the top of yahoo! answers 8)), but just in case:
Make sure to make System Restore Point, and if you have enough time, partition imaging is more safe.
This may take long time, so you should start imaging before going to bed ;D
There are some free soft that can do it.

EASEUS Todo Backup
http://www.todo-backup.com/

Paragon Backup & Recovery
http://www.paragon-software.com/home/db-express/download.html

Good luck, and take care... :)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: stuboy on October 13, 2010, 01:35:50 PM
I have been suffering exactly the same problem with DPC latency on my quad core XP SP3 machine with Emule running.
The problem does not occur when the following combination of modules are used:-

When i disable Avast all together my max latency is 220uS

I disabled each of the 7 shields and that made no difference!

Ok I have done the following now:-

File System Shield:- Stopped
Mail Shield:- Running
Web Shield:- Running
P2P Shield:- Running but Emule not being scanned
IM Shield:- Stopped
Network Shield:- Running
behavior Shield:- Running

This combination stops the problem with DPC latency, anyone provide anymore help on this?
Regards
Stu
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: silviucc on October 13, 2010, 02:27:32 PM
I would like to drop my 2c here on the DPC latency thing. For me, what happened was that I would get large spikes sometimes but I really couldn't understand why, after quite sometime I was able to link the problem to my GPU changing frequencies like when playing a game and doing and Alt+Tab, or watching a youtube video. Some people attributed this to also Intel CPU switching frequencies (speedstep)

I would not rule out bad drivers, but the above is worth a look.

Good luck.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: stuboy on October 19, 2010, 11:56:37 AM
OK I took your advise and updated both my Network interface drivers the Marvell and the Realtek 8169 there were updates for both and I installed the latest update of Avast.  So far the results seem encouraging. My highest latency for the last 2 days is 1804uS easily acceptable  8)
Long may it continue, I will keep the thread updated if it starts deteriating again as it sometimes took a few days.
Regards
Stu
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: silviucc on January 13, 2011, 09:24:03 PM
Going to resurrect this topic.

Using the latest AIS, had a linux distro torrent running in the background and was watching a movie. I noticed some weird sound but thought maybe something was wrong with the file, then wanted to watch video on youtube and noticed the same problem with those. Checked DPC latency and it was well above 8000uS. I closed utorrent no improvement then I disabled AIS for 10 minutes and latency went back to normal.

Also, it stayed low after AIS re-enabled itself.

I have the latest drivers for my onboard NIC, system specs are in the sig
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: DavidR on January 13, 2011, 09:32:00 PM
You don't say what build of avast5 you have, 5.1.889 is the latest (I don't know if that will make a difference) ?
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: silviucc on January 13, 2011, 09:33:26 PM
Seems I cannot access it. i get "The topic or board you are looking for appears to be either missing or off limits to you."
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: nmb on January 13, 2011, 09:35:24 PM
You don't say what build of avast5 you have, 5.1.889 is the latest (I don't know if that will make a difference) ?

I think that latency is different than this ??
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: silviucc on January 13, 2011, 09:39:12 PM
Yeah, I was talking about build 5.1.889
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: nmb on January 13, 2011, 09:46:04 PM
My post was directed at Sir DavidR's post, which he has edited and I posted before that. Sorry for the misunderstanding Silviu C.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Vlk on January 13, 2011, 10:30:21 PM
I can confirm there's a compatibility issue between the AIS Firewall and uTorrent. This will hopefully be addressed in one of the upcoming updates.

Thanks
Vlk
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: gzex on January 15, 2011, 03:21:27 AM
Are there issues if some other torrent client is used ?
is this problem utorrent specific ?
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: igor on January 15, 2011, 03:24:11 AM
That's unknown - but all the reports so far mentioned uTorrent.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: silviucc on January 15, 2011, 09:59:48 PM
One thing tho, I do not use AIS' firewall component. It's turned off... or is it ?
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: gzex on January 18, 2011, 02:31:24 AM
That's unknown - but all the reports so far mentioned uTorrent.

I think it's with all torrent applications , I just tried with  qBittorrent .
Same thing, as soon as there are some connections latency goes high and pretty soon it's over the top.
When exited from both applications , it calms down and then everything goes back to normal.
But as you know, you can't just download something and after it's done exit from application (seeding) , you just have to run it 24/7.

Please take care of it as soon as you can.

Thanks.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: wonderwrench on January 18, 2011, 04:45:23 AM
Just an FYI, Windows 7 has a bug that can cause high DPC latency unrelated to Avast 5. It looks to related to networking specifically ndis.sys. Some people never have the problem while others can't get away from it. It is most likely hardware related IMO but no one knows for sure. Someone claimed MS knows about it and a hot fix is available by phone support only and the fix is part of SP1. I tried to locate where I read this but can't for the life of me find it. See Google search results http://www.google.com/search?q=ndis.sys+causing+high+DPC+latency

Bill
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: gzex on January 18, 2011, 05:07:31 AM
That might be true and I don't doubt it.
However, I used many many firewalls and been running torrents for years, never seen this huge spikes with any of them.
OA is the one with similar problems (second to avast which is no.1 for sure) , but in OA it's not that huge , but it's large.
With Avast, after say 12hrs of usage you can't watch a movie anymore or listen to music, it is that high (DPC checker is all red with spikes over 8k)
Without using torrents , latency is normal , never goes above 120-130 , when you start using it, it slowly goes up and up, after hour or two it's 4k.
At that point sound starts to crack.

I mean, I'm not bashing Avast or anything, I'm using it and I want to use it, I like it's firewall, there is just this issue.

If what you said is true (hardware related) , how is it then that other firewalls are working fine, same setup, same OS, same everything.

It's something in Avast firewall driver / service.

Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: gzex on January 18, 2011, 04:13:23 PM
It's clearly avast driver , this is report from Latency Monitor :

One or more DPC routines that execute on behalf of drivers running in your system appear to be causing serious problems making your system unsuitable for processing real time audio. You are likely to experience audio dropouts, clicks and pops.
Time running:  0:02:37


Highest DPC routine execution time (µs):  5946
Responsible driver:                       aswNdis2.sys  (avast! Filtering NDIS driver, AVAST Software)
DPC count (execution time <500 µs):       6363480
DPC count (execution time 500-999 µs):    18
DPC count (execution time 1000-1999 µs):  11754
DPC count (execution time 2000-3999 µs):  2955
DPC count (execution time >=4000 µs):     14717

Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: silviucc on January 19, 2011, 01:53:31 PM
Yes, I got the same while using LatencyMon. aswNdis2.sys was the top DPC routine execution time. The funny thing is that I do not use AIS' firewall, it's turned off, and that driver still does funny business in the background.

However, I'm going to suggest that maybe , just maybe, there might be something wrong with WPF (windows filtering platform) since, some people complained of high DPC latency issues with MSE and avast seems to use WPF.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: DavidR on January 19, 2011, 03:26:32 PM
Turning off the firewall won't stop the low level driver from running, though I don't know how it would be doing anything if the firewall is disabled.

If you aren't going to us it then you should uninstall it, Control Panel, Add remove programs, Avast, Change Remove, Change and uncheck the firewall module, click Next and OK your way out, reboot.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: JoeB on February 04, 2011, 04:10:18 PM
I did some testing upon DPC Latency issues, seems there is something with Avast NDIS Firewall Filter Driver.

Windows 7 x64 Pro

Done with a Killer Xeno Pro, all tests are done by watching some videos on youtube, no bit torrent or p2p software installed on my system.

6.0.0.0 with the NDIS driver enabled, my first impression was that the Killer driver must be the cause.
(http://img411.imageshack.us/img411/4025/bf60.jpg)

So I tested a few drivers trough, and then it hit me to try disabling the NDIS driver all together.

6.0.0.0 with the NDIS driver disabled.
(http://img109.imageshack.us/img109/7752/noavast.jpg)

EDIT: To make sure I tried to remove AVAST and test with COMODO.
6.0.0.0 with COMODO's NDIS driver enabled.
(http://img686.imageshack.us/img686/5306/comodoi.jpg)

Tool used: http://www.resplendence.com/latencymon

NOTE: This is with the older 6.0.0.0 Xeno driver, the most recent release makes it look even worse for AVAST.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on February 04, 2011, 07:45:08 PM
Well, well, well when does this problem will end ?? :-X
My XP is still the same way ....
But I trust in AVAST, it is still the world's best.
End this problem,please..... ;)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: YoKenny on February 04, 2011, 09:14:20 PM
Well, well, well when does this problem will end ?? :-X
My XP is still the same way ....
But I trust in AVAST, it is still the world's best.
nd this problem,please..... ;)
No problem on my XP Pro system.  8)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: silviucc on February 05, 2011, 01:03:22 AM
Is that with or without a torrent downloading in the background YoKenny ?
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: JoeB on February 05, 2011, 01:54:02 AM
No problem on my XP Pro system.  8)
Your DPC latency is still pretty high, specially the peak.
Try to check it with LatencyMon

Check this ;) That is with Comodo's package
(http://img222.imageshack.us/img222/3641/captureiwn.jpg)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: YoKenny on February 05, 2011, 02:26:24 PM
Is that with or without a torrent downloading in the background YoKenny ?
No torrents for me!
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: YoKenny on February 05, 2011, 02:35:57 PM
No problem on my XP Pro system.  8)
Your DPC latency is still pretty high, specially the peak.
Try to check it with LatencyMon
See
Quote
NOTE: Because LatencyMon relies on ETW tracing it does not support any version or edition of Windows XP or Windows 2003 Server.
http://www.resplendence.com/latencymon_os
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Nesivos on February 05, 2011, 04:58:11 PM
So, I'm not Sherlock Holmes, but after almost two months I finally found out what the real problem with avast.
It's called DPC (Deferred Procedure Calls).
look at the undeniable proof.

Photo 1:
this photo you can clearly see how the DPC is absurdly high, the problem appears only 9 hours after leaving the avast using the scan of P2P shield.
That's what causes the problem of sound and video on youtube and on the computer.
My home PC is connected to 6 days a week 24 hours a day is why I can feel these problems more than others that turn off your PC.
The DPC is extremely high and could have been much higher if I had done more testing for a few hours.


Photo 2:
This picture is clear and transparent what happens when i turn off all the shields of avast, the DPC returns to normal and no sound problems, end more, some times the mouse pointer jumping from one point to another in screen.
I think all avast is causing the high DPC only to be turned on and this problem its worse even more if you use P2P shield or full system scan.

Test the DPC latency.
if you want to test it on your PC just download the DPC Latency Checker in this link:
http://www.thesycon.de/deu/latency_check.shtml
dont need install just download end use,put your tests here,iam using Windows XP/sp3/1G Ram/processor 3.2 pentium 4.

Persistent problem.
this problem with DPC is going on since the final version of avast was launched.
No one from ALWIL want to resolve it, and the worst part is that it must have thousands of users with this same problem and they dont have faintest idea what is avast which is causing sound problems in they computers, sound problems,slow system and the mouse pointer jumping from one point to another in screen.
I do not recommend to exchange of antivirus, avast still the best in the world but version 5 still far from the high reputation of version 4.8.

Solution
If anyone knows the phone of David Copperfield or Houdini please call them to do a magic to FIX this problem.
developers not Seems to be worried with the largest issue of avast at all times.
I hope in the next verssion this error in DPC ends.

if you are a visitor you will only see the photos if you register on the forum, is free,easy end fast.


G-d do I love this website. :)  Seriously.

It is like going taking technology classes for free.

Anyway I downloaded the DPC Latency Checker and have it running.

So far all shows green below 500us.

Windows 7 HP x64 AIS 5.1.889 all real time shields working

Computer never off unless the my internet connection goes down, which is rare.

I will keep the DPC Latency Checker up for a while and see if if the bars move out of the green

By the way it is my understanding at this point that high DPC Latency can be due to a bad or corrupted Windows installation.

Maybe even outdated drivers.  Though I am not sure about this one. :)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Nesivos on February 05, 2011, 05:07:19 PM
;) will its good that you already find a solution

first time i use it, the dpc pointing driver that going mad

so what is the point testing it at AV?

what i think is, avast is security software and not a device driver

if there is interference try to observe what is the cause of it. and what is the proper testing.

 ;D example: can you try-out swimming so that you will be good boxer  ??? ???  ;D

its the same:
a testing for device driver,  you test it in security software and what you got? interference only and try put another AV it will be the same ratings.

sorry for my words!!! just a point of view

Best Regards!!

its OK,is your point of view,I respect that.
but avast has services installed on the PC and I think also has drivers.
its not a coincidence avast scan a file and DPC latency go almost  to max.
thanks fo reply.

Just ran a scan of my "L" Drive which is where I keep all my data files.

During the scan which took about a minute the latency actually dropped by over 50% for the entire scan.

I will now scan my audio and video files about 127 GB which are on an external USB HDD and see what happens.

If I don't post the results it means that there was no negative impact on the DPC during the scan
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Nesivos on February 05, 2011, 05:12:57 PM
There are exactly 2 users (two) here in this forum complaining about this symptom. Not more. So I refuse to believe that it is a bug in avast... considering the posts of those 2 users.

+1 ;D
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Nesivos on February 05, 2011, 05:16:58 PM
Hey wonderwrench: it can't be, that you don't have this problem. Cako says that it is a flaw in avast, consequently you must have this latency. If not, it's a bug.  ;D
Maybe you should request a bug-update from alwil?

It is a bug but it may or may not be an Avast 5 bug. It very well might be a device driver bug in a hardware device that causes a conflict with Avast 5.
wonderwrench tanks again end ignore this user it just mess it up.( Zyndstoff)
Network Interface Card its Ok end updated.
my computer is always updated with everything, that's why I'm not going back to using version 396.

Question: How do you check to see if your drivers are up to date? Windows update? System or motherboard manufacturer? Non of these will insure you have the latest drivers. What NIC does your PC have. The problem you are having could be related to any device driver on your PC. To find the cause people having this problem need to list the hardware in there systems and see if any are common to all having this problem.

You can try DriverMax.

I use it and it works great for me.

Their is a limitation of 2 driver downloads a day in their free version, however I have never found that to be a problem.

http://download.cnet.com/DriverMax/3000-18513_4-10572602.html (http://download.cnet.com/DriverMax/3000-18513_4-10572602.html)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: CraigB on February 05, 2011, 05:36:23 PM
Nesivos, why sre you quoting stuff that is ten month's old, all this is just trying to bring your post count up  >:(
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Nesivos on February 05, 2011, 05:57:21 PM
personally I I spent my time in the latest 27 hours doing tests on my computer.
I installed the Device Doctor and guess what, any driver needs to be installed or updated.
I uninstall Avast 5 end install Avast 4.8 (latest version)
Avast 4.8 - low DPC latency.
I uninstall avast 4.8 and install kaspersky.
kaspersky - low DPC latency.
I uninstall kaspersky and install AVG.
AVG - low DPC latency.
I uninstall AVG and install Avast 5 version 396.
Avast 5 version 396 - low DPC latency.
I uninstall Avast 5 version 396 end install Avast 5 version 462.
Avast 5 version 462 - very high DPC latency. >:(
when I deactivated the P2P shield scan - low DPC latency.
well, the only thing left to do its downgrade the drivers, but I will not do.
I'm using Avast 5 version462.

My sister's computer:
have the exactly same result.
her computer has a conf. completely different from mine.

Next version of avast.
I'll wait for the next version and see if the problem continues, I will create another topic again, end again,end again , end again, end again..........
thank for everything guys.


Just curious

Why are you messing with Avast 5.462?

That is ancient history.

Current Config

Windows 7 HP x64
Firefox 4.0b10
AIS 5.1.889 all real time shields running

Programs running

1.  Thunderbird
2.  Firefox with 7 tabs open
3.  AIS 5.1889 doing a full scan of of Video and Audio files 127 GB on an external USB HDD
4.  uTorrent running and downloading one file about 15 kB or so
5.  Playing one YouTube streaming video

DPC remains consistently under 500us at between 125us and 300us, though it did spike up to around 500us when the Youtube video began to download.  After that and for the duration of the video the DPC remained under 300us.  It was a musical video about 4:30 in length

However I did get one spike into the Red when "SystemRestoreCreation" was completing.    SRC is a third party application that allows you to back up your registry on Windows 7.   Windows 7 has no functionality to just back up the Registry so I use this program and run it daily using Windows Task Scheduler.

I just manually reran SRC.  The only difference this time is there was no Video playing.  I got the same Red spike when it finished. Just one bar when the program finished and popped up its small window indicating that the backup was complete and successful.

No biggie since this is a 3rd party program that runs only once a day and the Red DPC was only one bar when the program completed.  However, it is something that I may look further into. :)
 



Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Nesivos on February 05, 2011, 06:01:25 PM
Nesivos, why sre you quoting stuff that is ten month's old, all this is just trying to bring your post count up  >:(

Just like Amir Johnson aka "The Warrior" doesn't keep track of his points and rebounds I don't keep track of my post count. :) :)

The reason I quoted it is because I just found the thread and was adding my two cents on the posts.

Anyway I am now done with this thread unless I find some relevant problem with my DPC.

Later ;D

Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: CraigB on February 05, 2011, 06:06:44 PM
Nesivos, why sre you quoting stuff that is ten month's old, all this is just trying to bring your post count up  >:(

Just like Amir Johnson aka "The Warrior" doesn't keep track of his points and rebounds I don't keep track of my post count. :) :)

The reason I quoted it is because I just found the thread and was adding my two cents on the posts.

Anyway I am now done with this thread unless I find some relevant problem with my DPC.

Later ;D


Do you not see the date of the post's you are quoting, you just asked cako why he is using and ancient version  ??? the date of his post is 26/3/2010.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: YoKenny on February 05, 2011, 09:18:10 PM
Do you not see the date of the post's you are quoting, you just asked cako why he is using and ancient version  ??? the date of his post is 26/3/2010.
What do you expect from a user that uses a MITS Altair 8800 ???
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Dwarden on February 06, 2011, 03:27:07 AM
guess he not realized the bug was fixed long time ago ...
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: JoeB on February 06, 2011, 11:40:19 AM
Your DPC latency is still pretty high, specially the peak.
Try to check it with LatencyMon
Quote
See
Quote
NOTE: Because LatencyMon relies on ETW tracing it does not support any version or edition of Windows XP or Windows 2003 Server.
http://www.resplendence.com/latencymon_os
What does it have to do with XP and 2003???
Your signature shows that your on 7.....



My point is that Avast's NDIS driver conflicts with some NIC drivers not the other way.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: YoKenny on February 06, 2011, 03:05:58 PM
Your DPC latency is still pretty high, specially the peak.
Try to check it with LatencyMon
Quote
See
Quote
NOTE: Because LatencyMon relies on ETW tracing it does not support any version or edition of Windows XP or Windows 2003 Server.
http://www.resplendence.com/latencymon_os
What does it have to do with XP and 2003???
Your signature shows that your on 7.....
My point is that Avast's NDIS driver conflicts with some NIC drivers not the other way.
I have both systems!
I have no problem on my XP Pro system but I see a problem on my Windows 7 system with DPC Latency Checker but it performs perfectly.  8)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: JoeB on February 07, 2011, 03:51:31 PM
What does it have to do with XP and 2003???
Your signature shows that your on 7.....
My point is that Avast's NDIS driver conflicts with some NIC drivers not the other way.
I have both systems!
I have no problem on my XP Pro system but I see a problem on my Windows 7 system with DPC Latency Checker but it performs perfectly.  8)
[/quote]
There is an impact caused by dpc latency spikes in some multiplayer games, which is mainly noticeable by random stuttering when fps is max and network latency is very low.
First thought would be that the issue is server side, but that is not the case for this instance.

I'm looking forward to check out the coming major version of the Avast Internet Security suite though, should be a chance for that it performs much better on Windows 7.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Nesivos on February 07, 2011, 09:43:56 PM
Found this thread on the Windows 7 Forum

Network usage causes high DPC Latency

Looks like the problem might me related to a NIC card driver and Windows


Quote
AHHHGHGHGHHGHHHGHGHG!!!!

I F---ing solved it !!!!

I made an account here just for posting this! I looked at this problem for 4 months and tried EVERYTHING!

All my symptoms are the same.. network traffic causes spikes. audio was jumping and popping. forget about HD video. every time I connected or disconnected to a network the spikes peaked at 33ms and stayed there for 5 minutes! you couldn't touch the computer. once every few hours when network traffic was very high (downloading at max speed) it froze completely and a reset was required. I tried every combination of driver and bios versions out there.
first of all there's this program
Resplendence Software - LatencyMon: DPC, ISR and pagefault execution monitor
it can tell you what driver exactly is causing the spikes
just run it - press play and go to drivers. there click on the highest execution to sort by it.
I saw that the major culprit was dxgkrnl.sys and ACPI.sys and nvlddmkm.sys and even USBPORT.sys. All of these had execution times higher than 1.0 ms. It was exactly the same as the latencies in the DPC latency checker.

apparently all (except the USBPORT.sys) are related to nvidia drivers. Specifically they are related to a feature that's called Powermizer. I found a tool to disable it easily:
Powermizer Switch.rar - File Shared from Box.net - Free Online File Storage
just run it click powermizer off and reboot!!! It solved everything for me! even the USBPORT.sys is under 0.4 constant now! (before they were all over 19.0ms and 18,000+ in dpc checker) check out my DPC! WOOOHOO! thank you everyone!!

http://www.sevenforums.com/network-sharing/52935-network-usage-causes-high-dpc-latency-4.html (http://www.sevenforums.com/network-sharing/52935-network-usage-causes-high-dpc-latency-4.html)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: silviucc on February 08, 2011, 12:34:57 AM
@Nesiovs That post is so old it should have grown a beard by now. Anyway, my DPC latencies went away after I unsintalled the firewall module from AIS. And yeah, they were caused by massive usage of the net connection. It also manifested with an Intel PCIe x1 NIC.

Powermizer causes DPC spikes on some machine, but what we were talking about here was constant high DPC latency while downloading something via torrents with the AIS firewall driver still loaded.

Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Cako on February 08, 2011, 02:54:34 AM
@Nesiovs That post is so old it should have grown a beard by now. Anyway, my DPC latencies went away after I unsintalled the firewall module from AIS. And yeah, they were caused by massive usage of the net connection. It also manifested with an Intel PCIe x1 NIC.

Powermizer causes DPC spikes on some machine, but what we were talking about here was constant high DPC latency while downloading something via torrents with the AIS firewall driver still loaded.



its old but is working and help other people with the same problem.....
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: lukor on February 08, 2011, 08:14:22 AM
Hi guys, I can confirm some DPC issues with AIS Firewall in the current version with massive connection counts. We are currently analyzing the problem and trying to come up with some fix, hopefully for the upcoming version 6.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: YoKenny on February 08, 2011, 02:36:50 PM
Hi guys, I can confirm some DPC issues with AIS Firewall in the current version with massive connection counts. We are currently analyzing the problem and trying to come up with some fix, hopefully for the upcoming version 6.
Will it be fixed in avast! Free ???

This pic is from my Windows 7 system.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Nesivos on February 08, 2011, 02:53:20 PM
Hi guys, I can confirm some DPC issues with AIS Firewall in the current version with massive connection counts. We are currently analyzing the problem and trying to come up with some fix, hopefully for the upcoming version 6.
Will it be fixed in avast! Free ???

This pic is from my Windows 7 system.

From what you have put in your signature I would suggest considering adding to the 1.5GB of memory.  My guess is that adding additional memory will significantly reduce your DPC Latency.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: YoKenny on February 08, 2011, 02:57:22 PM
From what you have put in your signature I would suggest considering adding to the 1.5GB of memory.  My guess is that adding additional memory will significantly reduce your DPC Latency.
As usual you have no clue what I am talking about as my Windows 7 system already has 4GB RAM  ::)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Nesivos on February 08, 2011, 03:09:18 PM
From what you have put in your signature I would suggest considering adding to the 1.5GB of memory.  My guess is that adding additional memory will significantly reduce your DPC Latency.
As usual you have no clue what I am talking about as my Windows 7 system already has 4GB RAM  ::)

I read the wrong RAM number.

I still don't think that the DPC Latency problems that people are experiencing has to do with AIS.  I don't know about Avast AV because I don't use it.

I quite thoroughly tested the DPC Latency on my computer and only noticed a single bar spike over 500us.*** The DPC checker was open by itself on my second monitor and easily visible the whole time so I didn't miss anything.  The checking took place with Firefox 4.0B10 having about eight tabs open, running 20 addons, downloading Torrents, running a AIS scan and playing a YouTube streaming video all at the same time.

*** In addition to one program, SystemRestoreCreation generating a single red bar spike when it completed. 
   

Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: YoKenny on February 08, 2011, 03:19:51 PM
I don't know about Avast AV because I don't use it.
If you do not use avast! AV then why are you here offering advice ???
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: DavidR on February 08, 2011, 03:25:16 PM
Hi guys, I can confirm some DPC issues with AIS Firewall in the current version with massive connection counts. We are currently analyzing the problem and trying to come up with some fix, hopefully for the upcoming version 6.
Will it be fixed in avast! Free ???
<snip>

Well if you are using the free version and the DCP issue is with the AIS version then I doubt it will fix that, I have no problem on my XP Pro system with avast free 5.1.889. The small spike was after restarting it all the previous columns were Green.

My little win7 netbook (Atom Dual core, 2GB DDR3 RAM, WiFi connection to router) with avast free 6.0.945 beta does have some issues, which is strange as it is very new and has no external devices hooked up so no device drivers required for them.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: YoKenny on February 08, 2011, 04:00:50 PM
Well if you are using the free version and the DCP issue is with the AIS version then I doubt it will fix that, I have no problem on my XP Pro system with avast free 5.1.889. The small spike was after restarting it all the previous columns were Green.

My little win7 netbook (Atom Dual core, 2GB DDR3 RAM, WiFi connection to router) with avast free 6.0.945 beta does have some issues, which is strange as it is very new and has no external devices hooked up so no device drivers required for them.
I am using avast! Free on the Windows 7 system and avast! Pro on XP Pro.
It makes no difference on Windows 7 if I use avast! V5.1.89 or the new beta but I am going to wait for avast! V6 official release on my XP Pro system as having to do a clean install of the beta is a bit of  a pain.  :(
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: DavidR on February 08, 2011, 04:22:42 PM
Well neither of those have the AIS Firewall in the current version as it isn't AIS, so I don't believe that avast 6 for free/pro will do anything for non-AIS related firewall issues. As you can see my win7 netbook has some latency but not as bad as yours.

So I would suggest following the notes in the bottom window of your image. Use Device Manager and check W-LAN adapters, modems, internal sound devices, USB Host controllers, etc.

There are tools to check your drivers and see if there are any updates available.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: lukor on February 08, 2011, 04:50:23 PM
Hi guys, I can confirm some DPC issues with AIS Firewall in the current version with massive connection counts. We are currently analyzing the problem and trying to come up with some fix, hopefully for the upcoming version 6.
Will it be fixed in avast! Free ???

This pic is from my Windows 7 system.

The problem I was talking about is specific to firewall and hence it does not exhibit any behavior in free version and the fix will not help there. DPC is not something bad in general. Many things in the system are going to happen on the DPC level, if you like it or not. For example most of the network related code is executed on DPC. And this is perfectly ok, what is not ok is when some piece of code is blocking others for too long. You might want to have it done quickly but sometimes it might be better to wait a while and let others to do their work for a while, this makes the system respond smoothly while performing other tasks in the background. Having some spikes of red in one program does not mean anything, if your system does not respond, your mouse is not smooth, your sound is choppy - that's a problem.

Lukas
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: RejZoR on February 08, 2011, 04:58:56 PM
Lukor, do you need any extra data or you already have everything you need, you just have to write a fix for it?
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: YoKenny on February 08, 2011, 09:56:16 PM
Having some spikes of red in one program does not mean anything, if your system does not respond, your mouse is not smooth, your sound is choppy - that's a problem.
System is very responsive, mouse is smooth, sound is clear in Media Player 12 - so no problem for me.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: JoeB on February 09, 2011, 12:17:58 AM

Will it be fixed in avast! Free ???

Does the free version even come with the NDIS driver which is purely for the firewall?
The AV itself doesn't have an issue regarding DPC latency.

DPC Latency Checker won't tell you where the problem is either.
You need to use LatencyMon or Xperf for XP together with sysinternals procmon so that you can track down the exact code causing the issue.

Loads of 8ms + DPC latency spikes are pretty bad, saying that they don't affect anything is a lie.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: gzex on February 09, 2011, 01:55:26 AM
Hi guys, I can confirm some DPC issues with AIS Firewall in the current version with massive connection counts. We are currently analyzing the problem and trying to come up with some fix, hopefully for the upcoming version 6.

Great news  8)
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: lukor on February 09, 2011, 12:42:14 PM

Will it be fixed in avast! Free ???

Does the free version even come with the NDIS driver which is purely for the firewall?
The AV itself doesn't have an issue regarding DPC

There is no firewall NDIS driver in the free version that has no firewall.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: coolsilver on March 20, 2014, 02:03:08 AM
Really getting tired of this freakin bug.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: DavidR on March 20, 2014, 02:22:40 AM
Really getting tired of this freakin bug.

Given that the last post in this topic was over two years and several versions ago, I would have liked to have though it would have been resolved by now.

That said I would say that it is probably better to start a new topic given this one is ancient and for very early versions of avast.

Are you really using AIS version 5 as in your signature ?
If so that may well be the problem as subsequent program updates will have changed the firewall module.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: coolsilver on March 20, 2014, 02:39:18 AM
Signature was outdated. I only come around most times when a beta is on going or get irritated by this issue.

I've posted in others previous but as a reminder of history I pulled this one back up.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: zerotox on March 20, 2014, 02:01:05 PM

[/quote]

Given that the last post in this topic was over two years and several versions ago, I would have liked to have though it would have been resolved by now.

That said I would say that it is probably better to start a new topic given this one is ancient and for very early versions of avast.

[/quote]

Actually there is a recent topic discussing the same problem:
http://forum.avast.com/index.php?topic=140679.30
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: DavidR on March 20, 2014, 03:41:51 PM
Signature was outdated. I only come around most times when a beta is on going or get irritated by this issue.

I've posted in others previous but as a reminder of history I pulled this one back up.

Unfortunately history isn't related, whilst it is/was DCP Latency so many avast versions later and a complete change in the firewall, etc. only confuses matters. So joining a more recent topic (as zerotox gave) or starting your own would have been better/ more related.
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: RejZoR on March 20, 2014, 06:14:45 PM
I'd like to know how things stand about this. I was thinking of buying avast! IS, but now i'm unsure. I need it to work flawlessly because i game a lot online and i can't have any latency issues, system or network...
Title: Re: DPC Latency will destroy the AVAST'S reputation ?
Post by: Djfe on April 06, 2014, 01:20:31 PM
I don't know what change at my pc in the last days caused the dpc latency to go down again, but I'm happy
What I did in the last days (might be one of those):
Avast Update (There was a program update it might have finally fixed those issues)
Malwarebytes Anti-Malware Search (in the free version) -> deleted a few files and registry settings containing pup (there was something about the firewall and antivirus, I think the notification in the windows action center was disabled, PUM)
latest Windows updates
Updated a lot of programs to their newest version
uninstalled avast grimefighter, browser-addon and "easy access and mangement" (it might be called differently in english, it's the last point in the middle column in uninstall tool)

If there is something else I forget to write about I will edit this post

Hopefully the issue gets fixed for you now as well ;)
I'm almost sure it was the avast update
I'm usign the free Avast version btw. so there might be issues in the avast firewall still (for the pro/internet security version), you have to test it on your system, because my issues might have been related to something else since I couldn't make out the source of the issue 100%


@RejZor this has nothing to do exactly with network and system latency
it's more like the responsivity of your drivers which cause sound cracks because the PC cannot handle the sound in real-time anymore because other unrelated drivers cause latency in the system
you probably won't recognize it while playing except for the sound issues (as far as I know)