Avast Free Antivirus Slows Down System & Internet Drastically

[producer]

Hi,
Since the last (and pre-last) update Avast Free Antivirus started to slow down the internet speed and also the PC drastically.
Whenever I run my browsers, Photoshop or any other frequently used program, the hard disc works at its full for few minutes and everything is almost freezing for a while, same when I close a program.
I looked at every single parameter in the settings and still can't find out a way how to fix this issue even just a little bit. Even changing the sensitivity of every shield to LOW gives no effect.
Also, every time I wake up my PC, Avast starts scanning, even my Floppy drive and there is no option to avoid that. Before the last two version updates there was no such a behavior.
I fully scanned my system and no any virus, malware or whatever found. If I stop the file or web shield, the system works great as ever before.
My PC is with mighty XEON 4 Core 2.88GHz, but since Avast Free Antivirus updated to its last two versions, my PC works like a 90's PC.
Please for any ideas and suggestions about solving this problem with Avast.
Big thanks in advance!

[Asyn]

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

[producer]

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

- Avast Free Antivirus 19.6.2383 (build 19.6.4546.494).
- Windows 7 Ultimate X64 SP1.
- No other security software.
- I use Avast Free Antivirus since few years ago. The "slow" issues described above have never happened before v19.6.2383 and the previous one. Before these 2 versions everything worked great for years.

[Asyn]

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.

[jaroslav.nix]

Hello Producer,  if you still see the slowdown after reinstallation of Avast (recommended by Asyn in previous post) and  have some time for experimenting, please help us with analysis, try to follow these steps:
   
- download windows performance toolkit from https://social.technet.microsoft.com/wiki/contents/articles/4847.install-the-windows-performance-toolkit-wpt.aspx
- install performance tool xperf (there are more tools in the toolkit)
- start logging in evelated CMD prompt, by command: "c:\Program Files (x86)\Windows Kits\10\Windows Performance Toolkit\xperf.exe" -on DiagEasy+DISPATCHER+Profile -stackwalk profile+CSwitch+ReadyThread -start avast -f \avast.etl -on 1492D477-3272-5C0C-D91A-C156CC3CD206 -start inet -f \inet.etl -on Microsoft-Windows-WinINet
- reproduce the problem (e.g. start the browser, photoshop, etc.)
- stop logging by command "c:\Program Files (x86)\Windows Kits\10\Windows Performance Toolkit\xperf.exe" -stop -stop avast -stop inet -d xperf.etl
- ZIP the output files xperf.etl file and upload it to out FTP server
- then please let me know the name of uploaded file

[producer]

Hello Producer,  if you still see the slowdown after reinstallation of Avast (recommended by Asyn in previous post) and  have some time for experimenting, please help us with analysis, try to follow these steps:
   
- download windows performance toolkit from https://social.technet.microsoft.com/wiki/contents/articles/4847.install-the-windows-performance-toolkit-wpt.aspx
- install performance tool xperf (there are more tools in the toolkit)
- start logging in evelated CMD prompt, by command: "c:\Program Files (x86)\Windows Kits\10\Windows Performance Toolkit\xperf.exe" -on DiagEasy+DISPATCHER+Profile -stackwalk profile+CSwitch+ReadyThread -start avast -f \avast.etl -on 1492D477-3272-5C0C-D91A-C156CC3CD206 -start inet -f \inet.etl -on Microsoft-Windows-WinINet
- reproduce the problem (e.g. start the browser, photoshop, etc.)
- stop logging by command "c:\Program Files (x86)\Windows Kits\10\Windows Performance Toolkit\xperf.exe" -stop -stop avast -stop inet -d xperf.etl
- ZIP the output files xperf.etl file and upload it to out FTP server
- then please let me know the name of uploaded file

Hi,
I will try soon to do what you asked me for.
The Windows Performance Tools (WPT) is part of the Windows 8.1 SDK and the Windows Assessment and Deployment Kit. So, will it run on Win7 x64?

[jaroslav.nix]

For windows 7 you can use some older version of xperf tool itself. I haven't find any link on the web right now, but you can try these installers (some of my older backup):
https://share.avg.com/nixj/users/xperf/xperf_x64.msi (for 64-bit version of Windows 7)
https://share.avg.com/nixj/users/xperf/xperf_x86.msi (for 32-bit version)