Latest definition update makes AvastSvc.exe's RAM usage (Commit KB) shoot way up

[REDACTED]

Okay so I have an old version of Avast! installed as I mentioned in some of my older threads and I'm very OCD about checking my system via monitoring tools how much RAM, CPU etc is being used at all times...

For the past couple of months AvastSvc.exe has pretty much always used between 70-75MB (Commit) on a startup of the system and after all the stuff on my boot is completed (such as services and Avast's rootkit scan etc) it's usually at about 84-89MB... and I monitor this on a daily basis...

So I went to sleep and when I woke up... Avast had updated it's definitions automatically... like it usually does... usually no cause for concern... usually I restart my PC and everything just starts again with the same usual cycle. But when I woke up and decided to restart my PC... AvastSvc.exe started up at 107MB (Commit)... and about 130-136MB after a complete boot which is almost 40-50MB more RAM... now I'm not sure why this is happening... but I assume it's something to do with these new definitions... because this wasn't happening last night...

I know this seems like a really stupid and irrelevant problem... but my OCD wouldn't allow me to just stand by and hope the problem went away after the next definition update. (I was thinking maybe it's a bug with them.)

Program version is 11.2.2262... (very old... yes I know but I didn't want to make the jump to the newer versions yet and this version has been running fine for a good amount of time)

I run Windows 7 64 bit Home Premium SP1.

Definitions are 160920-0... and were released at 11:06am today... (I had the older 160919 definitions last night and I didn't have this sudden memory spike.)

[Eddy]

See if a repair is changing things.
If not, perform a clean installation.

And I really advise to use the latest version.

[DavidR]

You would have a field day checking my system.

AvastSvc.exe is only 5th in order of RAM use by far the biggest RAM hog is Firefox and thunderbird, but even they in the greater scheme of things isn't of concern I still have plenty of RAM available. I have the same VPS version as you but I'm on avast 12.3.2280 on XP Pro. On my win7 32bit system AvastSvc.exe is 4th in order of RAM use, again firefox is the memory hog.

RAM is there to be used (to speed your system) and managed by windows, it only releases RAM if other functions need more. This to a certain degree is out of your hands and control, so I don't go looking unless I actually see a slowing of my system.

I know this will be hard for you, but 84-89MB even 130-136MB use against what RAM you have must be minuscule.

I never go hunting for problems unless one exists, e.g. there is something wrong with my system, slow etc. I only have 4GB of RAM on this system and I don't see any issues that would warrant investigate, e.g. system slow or actual error messages displayed to the screen.

I don't monitor the task manager nor do I monitor the windows event viewer for warnings or errors, to me they are soft errors, e.g. no actual error displayed to the screen, only when an error is displayed on a more regular basis do I

[REDACTED]

You would have a field day checking my system.

AvastSvc.exe is only 5th in order of RAM use by far the biggest RAM hog is Firefox and thunderbird, but even they in the greater scheme of things isn't of concern I still have plenty of RAM available. I have the same VPS version as you but I'm on avast 12.3.2280 on XP Pro. On my win7 32bit system AvastSvc.exe is 4th in order of RAM use, again firefox is the memory hog.

RAM is there to be used (to speed your system) and managed by windows, it only releases RAM if other functions need more. This to a certain degree is out of your hands and control, so I don't go looking unless I actually see a slowing of my system.

I know this will be hard for you, but 84-89MB even 130-136MB use against what RAM you have must be minuscule.

I never go hunting for problems unless one exists, e.g. there is something wrong with my system, slow etc. I only have 4GB of RAM on this system and I don't see any issues that would warrant investigate, e.g. system slow or actual error messages displayed to the screen.

I don't monitor the task manager nor do I monitor the windows event viewer for warnings or errors, to me they are soft errors, e.g. no actual error displayed to the screen, only when an error is displayed on a more regular basis do I

I agree, to a degree... I just found it odd that for about 2-3 months now... AvastSvc.exe has always ran at a stable RAM usage (between 85-89MB after a complete boot is done.) And now today it suddenly rose to 132-136MB after the latest definition update... it has literally NEVER ran at this high a RAM number before... (talking Commit (KB) also)... although the actual working RAM number is always 40,960MB... as always...

I'm just a little confused is all... as to what has caused this sudden and quite erratic rise in memory... (it went up by around 40-50MB which is quite a lot... not for my system as I have 8GB installed but it's still quite weird.)

And I'm really OCD about my system stats... I have my resource monitor and task manager tools open always... which is why I noticed it... I hate it when programs change their behaviour all of a sudden and it generally bugs me... I'm not sure whether it's the definitions or an Avast! Emergency Update that has caused Avast!'s behaviour to change (though the program itself seems to work as it normally would...) because I know that on occasion... the Emergency Updater can change some core files in the program and change it's behaviour as it's happened in other ways before... and I'm not sure of the definition files purpose either tbh... or whether or not the VPS files can change the way the program acts but there were a bunch of definitions about 3 weeks ago or so that kept on stopping the core Avast! services and causing them to fail so I don't know.

[DavidR]

What you have to remember is that the VPS updates isn't just the virus definitions, but includes engine and micro updates. So there is a possibility an engine and or micro update, could well be doing more in the running of avast.

Then there is as you mention the Emergency Update, which may just be a bug fix or something more substantial. These aren't to frequent, given the nature of the emergency is one that would correct something that otherwise couldn't be corrected in the engine and virus definitions update.

Either of the above could have an impact on the installed size and system resources required/used. Unfortunately there is no detailed documentation as to what has changed and how it might effect avast and system resources.

I haven't experienced any noticeable major increase in RAM from recent program and VPS updates, but then I never have my Task Manager open all of the time. What I'm monitoring is how my system feels/runs, not micro managing it. If there are noticeable slowing of the system, that gets my attention, not immediately, but if it continues over a period of time.

On my other system:
- Acer Aspire One, Win7 Starter (32bit) 10.1", 1024X600 screen, 2GB DDR3 RAM, Intel Atom N255 (1.5GHz dual core) CPU and 250GB HDD.

This is much less powerful and has only 2GB of RAM, but I have one svchost.exe entry that is running at 25% CPU virtually all of the time and I have been unable to pin down why. I can see what other services are running under that svchost entry (no avast items) and nothing that stands out as to why that would be using a lot of CPU %.

[REDACTED]

What you have to remember is that the VPS updates isn't just the virus definitions, but includes engine and micro updates. So there is a possibility an engine and or micro update, could well be doing more in the running of avast.

Then there is as you mention the Emergency Update, which may just be a bug fix or something more substantial. These aren't to frequent, given the nature of the emergency is one that would correct something that otherwise couldn't be corrected in the engine and virus definitions update.

Either of the above could have an impact on the installed size and system resources required/used. Unfortunately there is no detailed documentation as to what has changed and how it might effect avast and system resources.

I haven't experienced any noticeable major increase in RAM from recent program and VPS updates, but then I never have my Task Manager open all of the time. What I'm monitoring is how my system feels/runs, not micro managing it. If there are noticeable slowing of the system, that gets my attention, not immediately, but if it continues over a period of time.

On my other system:
- Acer Aspire One, Win7 Starter (32bit) 10.1", 1024X600 screen, 2GB DDR3 RAM, Intel Atom N255 (1.5GHz dual core) CPU and 250GB HDD.

This is much less powerful and has only 2GB of RAM, but I have one svchost.exe entry that is running at 25% CPU virtually all of the time and I have been unable to pin down why. I can see what other services are running under that svchost entry (no avast items) and nothing that stands out as to why that would be using a lot of CPU %.

Ahhh... well I didn't realise the VPS updates actually could affect the possible behaviour of the antivirus in general as well... I mean after the bugged definitions we got some weeks ago I had a general idea that this was the case... (remember the ones that made the Avast! Antivirus services shut down unexpectedly?)

I'm still not 100% sure if these new batch of definitions as of this morning affected the sudden memory spike... but I literally have changed no settings in my .ini or in the UI... once I find settings that work for me I will generally never modify them... so I'm not sure...

And yeah... I've heard of tonnes of people that have that svchost.exe CPU issue... there's a good amount of threads all over the net about it... I've luckily never encountered them... but I'm on Windows 7... though some cases have been on 7.

It's just strange about the memory thing though... yesterday before I went to bed I restarted my computer and the memory was at normal parameters... (71-76MB > 84-89MB respectively) and then when I woke up this morning and restarted this new behaviour began.

[DavidR]

That's the thing when you are taking this close attention, you are going to notice things that aren't actually critical. It shouldn't impact on your system performance.

That level of RAM use for a security application is not that bad (especially if you have adequate RAM installed), when you see that my firefox uses 1/2GB of RAM when we are talking of 132-136MB it is peanuts.

Windows manages RAM and the more you have the more it uses (unless you have changed windows settings for RAM usage) as that is what RAM is for, performance. Otherwise it is going to be constantly swapping what is in RAM to the pagefile on your HDD. That is something that is more of an issue than avastsvc using 132-136MB.

Note - The avast rootkit scan starts 8 minutes after boot (in previous avast versions, I can't confirm this is still the case) and shouldn't take that long. So windows permitting CPU and RAM use should reduce.

[REDACTED]

That's the thing when you are taking this close attention, you are going to notice things that aren't actually critical. It shouldn't impact on your system performance.

That level of RAM use for a security application is not that bad (especially if you have adequate RAM installed), when you see that my firefox uses 1/2GB of RAM when we are talking of 132-136MB it is peanuts.

Windows manages RAM and the more you have the more it uses (unless you have changed windows settings for RAM usage) as that is what RAM is for, performance. Otherwise it is going to be constantly swapping what is in RAM to the pagefile on your HDD. That is something that is more of an issue than avastsvc using 132-136MB.

Note - The avast rootkit scan starts 8 minutes after boot (in previous avast versions, I can't confirm this is still the case) and shouldn't take that long. So windows permitting CPU and RAM use should reduce.

It's just that as I said... previously... yesterday, infact... that AvastSvc.exe started at around 72-76MB on a startup of the system... and after the boot is complete (such as when the Avast! rootkit scan runs and everything is loaded into the memory) it was usually at around 84-89MB...

But as of today this changed and I'm not sure why... that's my main issue... why? My main issue isn't that the memory has gone up quite a bit... (it does bug me a little) but my main concern is why it did this in the first place.

From 72-76MB > 102-108MB on startup is a bit of a jump... and from 84-89MB > 130-135MB is as well... but if I only knew if it were the definitions that caused this then it'd be fine... and i'd get on with my day... but the fact I'm 0% sure what caused it... has me perplexed.

[DavidR]

Things change that we as users have no real knowledge of, but an average jump of 32MB really is tiny in the greater scheme of things. To find this when there is no real way if finding what changed when you have no detailed log of what has changed and how that change might be reflected in either RAM or CPU usage. Not to mention, there are other programs on your system and changes there could also impact on avasts use of CPU/RAM.

To expend a lot of time chasing that 32MB average, when the chance of actually finding the cause is slim at best, isn't a great use of your time - but it is your choice.

This is why I don't actively monitor the Task Manager or the Event Viewer, etc. I don't sit watching my system boot times either.

Your best monitoring if how your system is performing, if it is regularly/consistently slow then active monitoring is worthwhile. For smaller things the time spent in active monitoring, less so.

[Eddy]

What is saying that it is avast itself that is causing the very little higher memory use ?
Could very well be something that is causing avast to scan more.