Windows 7 Core Parking and Games (WoW)

[weevil]

Hey all. I just built a speedy new rig and was loving my performance in games like Crysis Warhead and Batman: AS. I installed WoW and found I was spiking between 8-20 FPS in Dalaran at max settings at 1850x1050. I searched the forums and found threads talking about a config.wtf var called processAffinityMask that defaults to 3, and how i7 quadcore users were having performance issues before changing that variable to 255. I tried that and had no luck, and finally found an article about Win7's core parking feature and how that can effect games.

The article suggests deleting a few registry keys related to core parking. I tried that and instantly went up to a smooth and constant 40+fps in Dalaran at max settings. Here's a link to the article: http://forum.cakewalk.com/tm.aspx?high=&m=1852473&mpage=1#1853037. Hopefully this can help some people, but I'm also curious as to other people's experience with core parking in Win7. Anyone see any pitfalls to disabling this?

EDIT: The author of the above mentions a better way of disabling core parking, instead of deleting the related registry keys you can set some of the key values without deleting them. Probably better path in case MS decides to allow us to disable it properly or fixes it to work with programs that are having performance issues with it.
http://forum.cakewalk.com/tm.aspx?m=1861804


Windows 7 Home Edition
Intel i7 920 @ 2.8GHz
2x Radeon HD 4870 DDR5 1GB
Asus P6T
3x 2GB Corsair DDR3 PC 1333
Corsair 850WTX PSU
2x 750GB WD Caviar Black HD
Cooler Master HAF 932

 

[r_manic]

I think the only pitfall is that you reduce the power efficiency of Windows 7. I don't understand why this issue cropped up though, as the core should only park when it really isn't needed, and I don't see this happening in such an intensive application like gaming.

 

[cjl]

I've got Win7 and an i7, and I haven't had any performance issues at all. I haven't tried WoW though - I'm not really into RPGs.

 

[weevil]

I think the only pitfall is that you reduce the power efficiency of Windows 7. I don't understand why this issue cropped up though, as the core should only park when it really isn't needed, and I don't see this happening in such an intensive application like gaming.

As I understand it, core parking attempts to keep your cpu from spinning up all the cores in normal use and tries to only put loads one or two cores until more are needed and spun up. Since I usually use this computer for gaming or encoding, it doesn't seem like it'd hurt my efficiency too much, though maybe I don't understand it properly. As far as gaming, I hadn't had a problem in the games I'm playing at the moment like Batman: Arkham Asylum, Crysis and Company of Heroes, just with WoW, and disabling core parking fixed that problem perfectly. I'm not sure why WoW alone has this problem, but I imagine it's due to the random CPU loads that come up in certain areas tied together with poor multicore support to begin with.

 

[Zoron]

Games aren't multi-threaded... so there is little benefit to having multiple cores when playing games. If you have multiple cores though, Windows can assign tasks to the other cores not being used when playing the game, freeing up more of the single core that the game is running on. There's actually very little software written to take advantage of multiple cores because of the difficulty in programming multi-threaded apps.

So it's a little confusing as to exactly why disabling something like core "parking" would increase performance in any game... unless you have a LOT of stuff running in the background that overwhelms more than one core. I'll have to try WoW to see if there's any issues on my rig... it seemed to run ok the last time I tried with the RC though.