Nod32 v4 has very high CPU useage during Computer Scan

The CPU shows ekrn.exe is using 87%-97% of the CPU when doing a scheduled scan of the files on the computer. There is an option under On-Demand computer scan > ThreatSense engine parameter setup > Other > Run background scans with low priority but checking this option has no effect. The priority of ekrn.exe in the Windows task manager still shows it running at Normal priority. How do I get the scan to run at BelowNormal priority? I can't really use the computer for anything else when ekrn.exe is using all of the CPU.

Using XP SP3 on a 2.4 ghz Intel P4.

 

Hi Wicker301,

When did you change the setting, during the scan or before? If before did you see if a reboot helped?

BFG

 

BDG,
A reboot does not help. Today I installed Nod32 v4.2.40 thinking it may solve the problem, but it doesn't. The "run at low priority" option has no effect on scheduled scans or manual scans. The windows task manager always shows ekrn.exe running at normal priority when scanning files and this uses up to 98% of the CPU. Try the Low Priority setting on your computer and see if it scans at low priority. My guess is that it doesn't. I can't change the priority in the task manager because it says "The operation cannot be completed".

 

I'd suggest scheduling a full system scan at the time the computer is idle.

 

I'd suggest scheduling a full system scan at the time the computer is idle.

Marcos,
It takes 9 hours to do a virus scan of the drives. I have it start at 3PM and it finishes up at midnight. At 1AM I have a backup starting. So to be without the computer from 3PM to midnight is a bit of a pain. It would be more tolerable if it wasn't sucking up 85%-97% of the CPU. Is there a way to reduce the CPU usage? Why doesn't run at a lower priority work?

Wicker301

 

Hi Wicker301,

Nine hours is a pretty long time for the scan to run. What settings have been changed from default? It's not scanning a backup directory is it? Is there a very large file or more than one that's included in the scan?

BFG

 

Nine hours is a pretty long time for the scan to run. What settings have been changed from default? It's not scanning a backup directory is it? Is there a very large file or more than one that's included in the scan?

BFG,
There are 340,000 files on this computer. I have excluded *.ISO and Acronis backup files *.TIB which are the largest files on the drives. I don't think I have changed anything in the default settings that would cause it to slow down. Are there any options I can try to speed things up?

Wicker301

 

Could you measure the impact of disabling archives/sfx archives on the scan time?

 

Ok, I'll do that later today. I have around 1500 zip files so that will shorten the scan somewhat.

Have you, or anyone else, tried the Nod32 setting to run scans in lower priority? Does it work? If I could run the scans in lower priority then at least I can use my web browser and email when the scan is running. As it is, it's locked up pretty tight with 87%-97% of the CPU going to ekrn.exe during the scanning process. Other programs will take quite a while to load.

Wicker301

 

I added *.zip to the exclusion list and Nod32 added
c:\*.zip
d:\*.zip
e:\*.zip
etc.

for each of the drives.

When the scan runs it still scans .zip files. Why?
Using Nod 4.2.40

Wicker301

 

You've excluded zip files in the root of all drives. In order to exclude zip files from scanning, add "zip" to the list of extensions excluded from scanning in the desired on-demand scanner profile.

As for running scans with low priority, this is completely controlled by the oper. system.