High cpu

[stig.joergensen]

Hi
Im using window 8.1 and avast 18.8.2356
Once a day i expirence very high cpu usage for extended period of time, 1-3 hours, and internet connection/browser becomes sluggish.

I have collected performance data, and will upload.

[Asyn]

Update to the latest version (19.1.2360): https://forum.avast.com/index.php?topic=224223.0

[DavidR]

The only thing to keep you on 18.8.2356 (and not updating to 19.1.2360) would be if you had windows XP. Since you haven't got that, I would proceed with the program update as Asyn suggested.

If this still happens with 19.1.2360, is there anything that you do or is run when this high CPU happens ?

What process is being recorded as having a high CPU usage ?

[stig.joergensen]

Its allready updated - and it happened again today. it might have happened other days while i was at work.

I happens when im ideling or away, when i come back it just show avast service running one full core of the CPU, and pretty much everything slows to a craw - only way out is a reboot (or wait for gods know how long)

[steve528]

I've been having this same problem for a while now, and it has become extremely annoying.  AvastSvc.exe hogs 99% of cpu at random times for no detectable reason, making my machine nearly unusable.  What is it doing?  Why?

[Asyn]

- Which Avast..? (Free/Pro/IS/Premier)
- Which version..?
- OS..? (32/64 Bit..? - which SP/Build..?)
- Other security related software installed..?
- Which AV(s) did you use before Avast..?

[inversenets]

On Latest FREE here

Windows 7/64 SP1 patched latest

Google - latest as of 21/1

Hit news sites like Bloomberg news (plus others) and AvastSvc will max. 100% then back off but then sporadically max or hit +25% for no apparent reason.

Plug-in uMatrix and it strips the underlying crap out of the packet stream and we have something close to normal.

Bit Defender look better - less sensitive to the BS.

Could swear was as of the latest upgrade in Avast.

Pulled latest MS monthly roll up - no joy.

Is an OLD PC but was fine until very recently and BD (full version) looks better in comparison.

No other sec.apps running.

[Asyn]

First, be sure to get rid of all remnants of your prior installed AV(s)..!!
-> https://support.avast.com/article/11/

Then:
1. Download Avast Free Antivirus: https://files.avast.com/iavs9x/avast_free_antivirus_setup_offline.exe
2. Follow instructions: https://www.avast.com/uninstall-utility (Run this tool for all prior installed Avast versions..!!)
3. Reinstall Avast with the downloaded installer from point 1.
4. Reboot.

[kwiq]

Hi  inversenets and stig.joergensen,
to find which component is responsible for such huge CPU usage we would need to capture performance log.

1) download windows performance toolkit (https://social.technet.microsoft.com/wiki/contents/articles/4847.install-the-windows-performance-toolkit-wpt.aspx) - just install performance tools xperf !
2) Run cmd line as admin and type : xperf.exe -on DiagEasy+DISPATCHER+Profile -stackwalk profile+CSwitch+ReadyThread -start user -on 72AA3505-D4D6-4527-A088-92534DA1082C   (xperf is usually located at c:\Program Files (x86)\Windows Kits\(Sdk number)\Windows Performance Toolkit\xperf.exe)
3) Wait for CPU peak
4) xperf.exe -stop user -stop -d xperf_merged.etl
5) Upload as inversenets_1_2019_xperf_merged.etl file to avast ftp

Thank you for report !

[steve528]

That link for the toolkit no longer works, but you can try go.microsoft.com/fwlink/p/?LinkId=526740

I haven't had a chance to run the new-possibly-improved-posssibly-useless toolkit yet, but the Avast-running-amok problem continues.  It is at this minute gobbling 99% of CPU according to task manager.  Sometimes I can make it stop by rebooting, and sometimes not.

[kwiq]

Hi,
link updated.
Just type xperf windows7 and google will do the rest :-) !.