Avast WEBforum

Consumer Products => Avast Free Antivirus / Premium Security (legacy Pro Antivirus, Internet Security, Premier) => Beta - Avast => Topic started by: Eddy on February 18, 2015, 04:24:36 AM

Title: svchost / dnsrslvr.dll problem
Post by: Eddy on February 18, 2015, 04:24:36 AM
Seems like I found a bug/problem with the latest beta version (2015.10.0.2209)
When avast starts when booting a system there is a instance of svchost that is using 99% of the cpu resources.
Process explorer shows it is hosting dnsrslvr.dll
Killing the process solves it and avast seems to continue working without a problem.
Disabling the shields, waiting a bit and enabling them again doesn't solve it.

Definitely something to look at i.m.o.
Title: Re: svchost / dnsrslvr.dll problem
Post by: DavidR on February 18, 2015, 03:57:46 PM
The latest beta is 2015.10.2.2210 (or that is how it is reported in the UI about/update). Worth checking if this is still in the R2 Beta2 release 2015.10.2.2210.
Title: Re: svchost / dnsrslvr.dll problem
Post by: Eddy on February 18, 2015, 06:26:10 PM
That is the one I have installed and is giving the problem.
Title: Re: svchost / dnsrslvr.dll problem
Post by: DavidR on February 18, 2015, 06:51:40 PM
That is the one I have installed and is giving the problem.

So basically the version number you gave in the first post is incorrect as that is why I posted.

Quote from: Eddy
Seems like I found a bug/problem with the latest beta version (2015.10.0.2209)
Title: Re: svchost / dnsrslvr.dll problem
Post by: lukor on February 19, 2015, 09:27:07 AM
Hi,
and the OS is?
Thanks.
Title: Re: svchost / dnsrslvr.dll problem
Post by: Eddy on February 19, 2015, 05:02:06 PM
OS is windows XP SP3

Report created with avastsupportR2.exe has been uploaded:
20150219_1549_VZG8Z_2800414375

Attached is a overview of my system specifications (and other things)
Title: Re: svchost / dnsrslvr.dll problem
Post by: lukor on February 21, 2015, 01:02:10 AM
Eddy thanks,
I was asking since dnsrslvr.dll seems much like DNS :-) and therefore if anything, interaction with SecureDNS could be expected - apparently not in your case, as we don't have that in XP.

Will keep thinking about the possible cause. Lukas.
Title: Re: svchost / dnsrslvr.dll problem
Post by: Eddy on February 21, 2015, 04:17:59 AM
Update, the problem is also in the RC1.

Yes, that was my thought also Lukor.
But I don't have secure dns or anything like that installed.

Just a thought...
When avast loads/starts the secure dns part is not looking what OS is being used.
If it is XP (or any other not supported OS), prevent it to load.
Title: Re: svchost / dnsrslvr.dll problem
Post by: lukor on February 22, 2015, 08:39:17 PM

Just a thought...
When avast loads/starts the secure dns part is not looking what OS is being used.
If it is XP (or any other not supported OS), prevent it to load.

Eddy, the driver providing stream filter and securedns is not even installed on XP.
Title: Re: svchost / dnsrslvr.dll problem
Post by: Eddy on February 26, 2015, 08:50:30 PM
Some more information I found:

It only happens when (re)booting.
On my systems it takes about 20 minutes before cpu use goes back to 0 for this instance of svchost.
According to the taskmanager, it is using a maximum of (give or take a few bytes) 18.500kB with almost 20.000 kB.
The memory use is increasing with steps of (roughly) 20 - 60 Bytes till it reaches the above values.
Since dnsrslvr is causing it, it seems to me that it has to do with packets that are send (to a avast server?).

Edit:
Problem is still there with the RTM