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Old 2012-03-02, 16:47   #1
kladner
 
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Question Mystery kernel activity hampering mfaktc

I suppose this could be put in Software, but since it impacts mfaktc I'll try here.

On a few occasions I have noticed that my two mfaktc instances have slowed down significantly. They run on a GTX460, in a Phenom II x6 system, Win7-64, with affinities assigned.

Last night I saw the slowdown, and went first to Task Manager, Performance tab. I have this set to show kernel times, and there was quite a lot visible. I checked things like Norton, but it did not seem to be doing background scanning.

This morning, it was still going on. I looked through Processes in Task Manager, but only the usual P95 and mfaktc were showing significant activity. Resource monitor was not much more help, except that I was able to pin down that a service(s) was consuming about one core's worth of CPU: 16-17%. I should have taken more complete notes, as I can't say specifically what the consumer was. It was not an immediately intuitive name.

A reboot put a stop to it, at least for now. Malware scans did not turn up anything. I determined that it was not a backup running.

Has anyone else experienced something along these lines, or does it suggest lines of inquiry?

Last fiddled with by kladner on 2012-03-02 at 16:49
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Old 2012-03-02, 17:21   #2
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I have had, on occasion, something similiar to this, one core maxes out and task manager says it is from NT kernal and system. I did a Google search and the recommended solution was to reboot. I have only had it happen 5 or 6 times since I started here though, and only on 2 or 3 of my systems (the ones I use most for other things while running P95 & mfaktc)
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Old 2012-03-02, 18:44   #3
kladner
 
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Quote:
Originally Posted by bcp19 View Post
I have had, on occasion, something similiar to this, one core maxes out and task manager says it is from NT kernal and system. I did a Google search and the recommended solution was to reboot. I have only had it happen 5 or 6 times since I started here though, and only on 2 or 3 of my systems (the ones I use most for other things while running P95 & mfaktc)
Thanks! This is certainly a machine that does lots of other stuff at times. Next time I see it I'll try to gather more specific information.

My main concern when I see unexplained activity is that something nasty might have snuck in, and is busy spamming or DDOSing, etc.
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Old 2012-03-02, 21:09   #4
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Windoze.
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Old 2012-03-28, 18:34   #5
kladner
 
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I found one culprit today: Windows Search Indexer. It was grabbing around 5% CPU, and most of it seemed to be coming out of mfaktc's share of CPU (normally 15-17%). This was causing GPU usage to oscillate rapidly between 55 and 98%. 1 mfaktc and 1 CuLu 2.0 in polite mode were running and CuLu was not affected. But mfaktc slowed way down.

I stopped the Windows Search service and the problem went away. I guess I might let it run occasionally, but too often it is disruptive .
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Old 2012-03-29, 02:53   #6
LaurV
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Quote:
Originally Posted by kladner View Post
...Windows Search Indexer....
Huh! turn that stupid-idiotic-software off! That is one thing I can't stand on windows, and I always turn it off. Type it in google, there are tips about how to do it. If you use file browser other then explorer (I use total commander from Ghisler) then it makes no difference in search speed if you turn it off.
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Old 2012-03-29, 02:59   #7
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Quote:
Originally Posted by LaurV View Post
Huh! turn that stupid-idiotic-software off! That is one thing I can't stand on windows, and I always turn it off. Type it in google, there are tips about how to do it. If you use file browser other then explorer (I use total commander from Ghisler) then it makes no difference in search speed if you turn it off.
Thanks. I agree. I'll have to look up "total commander from Ghisler."
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