World of Warcraft CPU usage.

GotNoRice

GotNoRice

[H]F Junkie
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I was playing WoW today, and had task manager up on my 2nd display so that I could keep an eye on Ram usage (trying to get an idea if going to 2 gigs will help things or not). While I was playing though, I noticed that the CPU usage was hovering between 30% and 35%. Since I have Xeons with hyperthreading, 25% cpu usage essentially represents 100% CPU usage for one processor. Usually with games it does not go higher than 25% at all.

Does anyone have any idea why it appears to be utilizing SMP at least partially? Could this simply be the result of using the new 5.12 catalyst drivers? Does WoW run stuff like the sound engine in another thread like UT2004? WoW doesn’t actually support SMP, does it?
 
When you're gaming, your system doesn't shut down the rest of the processes running. Also, you might want to check this too, does the load seem evely distributed among your processes? I've noticed at times windows seems to juggle a high cpu usage program between processors. If you get smp seesaw, you can isolate it to a single cpu which should help. I can get screen shots to back up my "juggling" theory too.
 
/agreed with above

I've seen Windows, especially while gaming, specifically transfer system processes over to the 2nd processor while keep the priority one (aka the one Im using) on the primary proc.
 
Affinity may or may not help -- it often doesn't.

Affinity will request that Windows run the process on only one processor. If the other processor becomes availalbe, setting affinity means that it won't be scheduled until the desginated process is free.

Indeed, you can see Windows move a thread from one processor to another and back. It does this because it figures that even given a penalty for the cold cache, it's better to let the thread run again. Otherwise, it has to wait for the affinitized proessor to become available. The scheduler figures that delay is becoming runnable is worse than the penalty for losing cache population.

If your game is using slightly more than one processor it's hardly making great using of SMP. The CPU usage shown in Task Manager is for the whole system: task manager itself is taking CPU to draw its graphs and read its measurements, and the OS and its services have work to do, and so on.

It's possible that your game somtimes does have more than one thread which becomes runnable concurrently, but the low CPU time over a single processor's worth of activity suggests that it's just happenstance.

If you want to figure out what's going on in more detail, you should use PerfMon
 
i can tell you that 2GB of RAM does wonders for WoW. i only had 1GB on my old machine, and sometimes i'd get hard drive thrashing when alt-tabbing back and forth between WoW and windows, but on my current machine, it's as smooth as butter.

WoW also only used one of the cores on my machine, but things might have changed with some of the newer patches and driver releases.
 
Aigh... driver releases from ATI and Nvidia are improving multicore support greatly. And I'll second the vote for 2 gigs of ram. Makes a tremendous difference in Wow. Really eliminates lag in IF.
 
dekard said:
Aigh... driver releases from ATI and Nvidia are improving multicore support greatly. And I'll second the vote for 2 gigs of ram. Makes a tremendous difference in Wow. Really eliminates lag in IF.
Click to expand...

The multicore support from nvidia and ati won't necessarily help performance, that's still limited by the game programming. Most likely that's to improve stability.
 
mikeblas said:
The CPU usage shown in Task Manager is for the whole system: task manager itself is taking CPU to draw its graphs and read its measurements, and the OS and its services have work to do, and so on.
Click to expand...

I was looking at it using the processes tab, and looking at the CPU usage of each individual process.
 
Actually some interesting things are happening in this field. Both the green team and the red are delivering fps increases due to multithreading their drivers. I've been seeing numbers in the 10-15% range, which is impressive.

defakto said:
The multicore support from nvidia and ati won't necessarily help performance, that's still limited by the game programming. Most likely that's to improve stability.
Click to expand...
 
One related question, I just built a 4400+ X2 system with 2 gigabytes of RAM and a 7800GT. I still get load lag in IF - only place in the game I still do, I think its more of a network related issue than graphics since I get 64FPS throughout the game and rarely dip to the mid 40s in intense situations (BWL and MC bosses, big PvP fights).

Anyone know of a solution to IF character/item load lag?

Thanks,
George
 
Load lag is a harddrive issue. Not cpu bound. Also, start a new thread for a new question, especially since you are not the original poster. Makes it more likely you'll get an answer and makes it easier to find the thread.
 
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