High cpu

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.

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

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 ?

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)

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?

  • 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…?

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.

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.

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 !

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.

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