File System Shield Issues

[websave]

Hello, I have noticed that if you check "Test whole files" avast starts using 80-90% of my CPU. I know it warns you that it will be slow but why would they put it there if it is going to lag up your PC badly? Is this normal?

[DavidR]

It rather depends on your system spec (OS, CPU and RAM ?) as to how likely it is to effect system performance and resources. So it isn't possible to say what is normal or not without more detailed information, the above info and what type of scan you were running and if that also included scanning archives and for PUPs also.

Personally I feel that the Quick scan defaults are more than adequate for most peoples needs.

[websave]

It rather depends on your system spec (OS, CPU and RAM ?) as to how likely it is to effect system performance and resources. So it isn't possible to say what is normal or not without more detailed information, the above info and what type of scan you were running and if that also included scanning archives and for PUPs also.

Personally I feel that the Quick scan defaults are more than adequate for most peoples needs.

OS: Windows 8 Pro 64-bit
CPU: Intel Pentium
RAM: 4 GB

[DavidR]

Depending on the clock speed and if it is a multi core Intel Pentium (?), your system in theory should be up to high intensity/resource applications running.

But I guess the avast warning is very valid, try it if it is too heavy, reverse it.

[websave]

Depending on the clock speed and if it is a multi core Intel Pentium (?), your system in theory should be up to high intensity/resource applications running.

But I guess the avast warning is very valid, try it if it is too heavy, reverse it.

Clock speed: 3.40GHz
Core (more detailed): Intel Pentium D CPU

[DavidR]

A handy reference if you can manage to find the equivalent System Properties as that gives detailed CPU information or a handy little utility CPU-Z http://www.cpuid.com/softwares/cpu-z.html very detailed CPU information.

That said your CPU isn't a slouch, but it the test whole files seems too much for it.

I just ran a Quick scan with test whole files, it took just over three minutes 0:03:34 for 6.8GB 2147 files 5706 folders, this is generally the same as my average for a Quick scan, so for me not much difference. I haven't done this for a Full System Scan yet as I rarely run this scan, but when I do it isn't too long either as I don't have masses of data on my system, very little in the way if media files or images. I don't collect tones of applications if it isn't used often, generally it will be uninstalled.

[DavidR]

Update, Just ran a Full System Scan whilst working on the forums.

Time 0:10:56
Files 98987 Folders 7461
Data tested 26.6GB

Now this may actually have taken a bit longer as it alerted on some spam/phishing database files. Once avast makes a detection it automatically switches to high sensitivity, which could mean that the scan takes longer. However, I have all of my scans set to High Heuristic Sensitivity anyway so perhaps it didn't have so much of an impact.

Edit: I don't know how far different my core2due CUP is from yours, but it doesn't seem to effect my system as much as yours. As avast says this could have an impact if you have lots 'large' files, which I probably don't have lots.

I don't know what your scan settings are, but here is a suggestion:
In the scan settings > Performance > Persistent Cache, enable the 'Store data about scanned files in the persistent cache' (I think this is off by default) and the 'Speed up scanning by using the persistent cache' (I think this is on by default). This after a few scans should populate this cache and speed up scans.

Scroll down a little in that same screen and on the File access sub-section try enabling that option, this should improve scan speed.

[websave]

Update, Just ran a Full System Scan whilst working on the forums.

Time 0:10:56
Files 98987 Folders 7461
Data tested 26.6GB

Now this may actually have taken a bit longer as it alerted on some spam/phishing database files. Once avast makes a detection it automatically switches to high sensitivity, which could mean that the scan takes longer. However, I have all of my scans set to High Heuristic Sensitivity anyway so perhaps it didn't have so much of an impact.

Edit: I don't know how far different my core2due CUP is from yours, but it doesn't seem to effect my system as much as yours. As avast says this could have an impact if you have lots 'large' files, which I probably don't have lots.

I don't know what your scan settings are, but here is a suggestion:
In the scan settings > Performance > Persistent Cache, enable the 'Store data about scanned files in the persistent cache' (I think this is off by default) and the 'Speed up scanning by using the persistent cache' (I think this is on by default). This after a few scans should populate this cache and speed up scans.

Scroll down a little in that same screen and on the File access sub-section try enabling that option, this should improve scan speed.

I believe you may have been confusing it with the anti virus scanner. I meant the "File System Shield" as in real time protection.

[DavidR]

Yes that is the case, confusion reigns - but the principal would be the same and was/is a quick way to see if there is an impact.

Yes it is going to place an additional resource load on your system, but many systems may be able to cope with that and an on-demand scan would be an extreme example (of testing it) and in not seeing any major I would hope that it would be the same for on-access scanning.

That said, it also brings a whole lot of other issues into the fray, such as what other applications are running (basic background resource use excluding avast), have you applied that to all avast shields that have it as an option. e.g. the web shield also has that as an option and that is possibly going to be the most active shield.

But given that you are experiencing high resource use I would set it back to the defaults and leave it at that.