Odd Performance Behavior 2! CPU Edition

[undrgrnd]

This is just a repost of the original Odd Performance Behavior. I'm afraid new people to the scene won't want to read through tons of old posts so I'm going to summarize it all here and hopefully we can go from there.

A couple months ago (After upgrading to a Core 2 Duo) I noticed that I was having some performance issues with games. They'd go from 60+ FPS down to 5 FPS at seemingly random times and for no reason. The first few suggestions pointed to the power supply so I got a new one, which didn't solve the problems. The second idea was that the RAM's voltage requirement was too high for this motherboard, so I bought another gig of RAM with the 1.8v requirement. This solved odd startup issues but not the performance.

Now I've opened up the Windows Performance Monitor and started looking at what could be the cause. When the lag spike starts to occur the only thing I noticed change (although it was a drastic change) was that the %Privileged Time and the %User Time switch spots. I googled them and what I found was an interesting read:
Microsoft TechNet Information

And yet... raises more questions than there were initially. Why, in the middle of a game, would it switch modes on me. It looks like it starts in User Mode and then when it switches to Privileged Mode thats when the lag spike occurs.

If anyone can provide information on these two modes, I've never heard of it before I'd appreciate it - and of course ideas about the problem at hand and how to fix it. I'll do some more monitoring to see if I can find anything and post some screenshots of the performance monitor during the spikes if I can.

%Privileged Time : Which goes from about 20 to 40
and
%User Time: which goes from 40 to 20.

 

[undrgrnd]

Woah!

 

[firemist]

undrgrnd, the shift in processor time between privileged and user is interesting and may give a clue. From the Microsoft article it states

"I/O operations and other system services run in privileged (kernel) mode; user applications run in user mode. Unless they are graphics-intensive or I/O-intensive (such as file and print services), most applications should not be processing much work in kernel mode."

which to me says either a service not related to the game (anti-virus, internet automatic update checks, malware, etc) is using the additional time or the system is stalling on I/O or sevices used by the game.

My best guess would be one of your programs is checking for updates on a way to frequent basis.

Can you check for scheduled update checks that may be running as services and shut them down as a check? If one of these is checking every hour or so it is too frequent and will slow the system when it does. You should be able to set the frequency if this is the case. If you can catch it when the shift occurs you may be able to look at the task/process manager and tell what is using the time.

If it is not this then it must be the system doing I/O retries because of errors. Check your system logs and see if anything is reported.

Good Luck