Hello, thank you for reporting. Would it be please possible to provide us performance recording for such situation, so we can analyse which Avast component is responsible for this:
https://forum.avast.com/index.php?topic=237567.0
Thank you.
Yes, I shall.
The avast-log.rar is uploading to your ftp now.
Thank you Peter52, are you sure the performance log is collected from the moment when you experienced the aswToolSvc issue, because I can see the only one process consuming almost 100% of the disk and its vmware-vmx.exe. You can have a look by opening the log in WPA (Windows Performance Analyser).
Not not the moment of, it happens randomly so it takes a minute or so before I catch it and start the logging. There’s no way I can anticipate the start, is that what you require? Also, I wasn’t running VMware at the time, I’ll have a look at the log.
Hmm, yes I see that. I guess I was running VMware but that was an unusual situation, I normally don’t. I’ll try again, I did an uninstall/reinstall yesterday as well so maybe that had some effect on it. Thanks Jaroslav, I’ll report back.
Jaroslav,
I’m uploading now a log file of the disk activity following a reboot. I ended the avasttools.exe during the logging so I would really appreciate it if you would have a look and let me know what you find. I did do an uninstall and reinstall a couple of days ago.
Thanks.
Use/Pick a unique name (and post it here), so Jaroslav can find it. 
File name is: avast-log_Stopped_AvastTools.rar
Thanks
Any update? I’m not too versed in reading the log file but it certainly seems as though aswToolsSvc.exe is the process that’s predominant here. I had to stop the service because of what it’s doing so I’m feeling unprotected. I’d like to get this resolved.
I am sorry for my late reply, I haven’t receive email notification from forum. Thanks Asyn for pinging me.
Thank you for the logs, it’s very helpful. The issue is connected to TuneUp scan running on background. I will make sure the issue is reported to TuneUp team and fixed as soon as possible. One more thank you very much for your patience and help with analysis.
Does the TuneUp scan run on all systems even if you selected not to install the CleanUp module?
Hi All. Thanks for report. We are looking at the issue and it seems that problem is that directory which is in our cleaning definitions has quite a lot of subdirectories and the scanning is taking quite a long time. We are working on solution and we will do our best to get it released as soon as possible. Bob regarding your question. Disk cleanup scanning module is part of AV smartscan which means that such scan can run even if cleanup is not installed.
Thanks for the updated information Lubos-78.
Is there currently any way to stop this scanning process till a solution is found?
Im not sure since this is question for AV development. I do not think that user can do it in UI. I will try to find solution with AV developers.
Thanks. 
Hello Peter52, removing cleanup component from AV setup tree should fix it. Open AV settings->Troubleshooting->ADD/MODIFY COMPONENTS->uncheck Cleanup and click on CHANGE button.
Thank you Petr, I’ve removed the component. If there is any further problem I’ll post back. I should mention that I run Avast on other systems as well and this is the only one exhibiting the behavior.
I think it would be helpful if component selection during setup were part of the installer as I would have saved myself many hours of effort had the option been known as I would not have installed the cleanup component initially.
If you do a CUSTOM install, you get the option to choose what to install and what to omit.