Affinity

[hassata]

Hi:

 

Been out of the loop for a while. Do we still need DCS Max or the Affinity trick post-patch?

 

Thanks

[Nate--IRL--]

No, fixed in the patch.

 

Nate

[Celo63]

Patch 1.0.1a readme

http://forums.eagle.ru/showthread.php?t=43547

 

Quote: * Vista users using multi-core systems will now have affinity automatically set to use all cores.

 

I presume XP users still need the DCS Max utility?

[nemises]

there is no benefit to using multiple cores on XP...only Vista and win7

[Waldo_II]

there is no benefit to using multiple cores on XP...only Vista and win7

 

Last I checked on the three dual-core Windows computers at my house, both 32-bit and 64-bit, and every dual-core Windows computer at my friends' houses, my school and public library, that is BS.

 

 

Also, this.

[Nate--IRL--]

Last I checked on the three dual-core Windows computers at my house, both 32-bit and 64-bit, and every dual-core Windows computer at my friends' houses, my school and public library, that is BS.

 

 

Also, this.

 

Well when DirectX 10 is made for XP you'll see the benefit Vista and 7 get. Until then the affinity setting has no effect in XP.

 

Nate

[Waldo_II]

Well when DirectX 10 is made for XP you'll see the benefit Vista and 7 get. Until then the affinity setting has no effect in XP.

 

Nate

 

 

In what way is CPU affinity related to the allocation of limited tasks to the GPU related?

 

The difference between DX9 and DX10, beside new graphics libraries, is the ability to allocate a limited number of tasks to the GPU, decreasing CPU load. This only happens when programmed to, and works for a limited number of tasks due to the relative inflexibility of even more recent GPUs, despite the recent surge in ability brought on by newer architectures such as nVidia's G80, G92, etc.

 

CPU affinity is what core a single thread of execution is assigned to. Single-thread programs usually assign themselves to whatever core is not being used as much as the other(s). What DCS Max and the recent version of DCS.exe did was assign, by a more efficient process, what affinity they should have.

 

Your statements haven't made any sense. Assigning CPU affinity certainly can have performance effects. If you assign every single program to core 0 and a single program to core 1, then that single program will run incrediblyl smoothly because it has that core all to itself. I cannot imagine why anyone can believe that wouldn't work.

 

In addition, DCS: Black Shark doesn't even use DX10. It doesn't matter what operating system, it doesn't use DX10, only DX9.0c. All non-graphics related processes are assigned to the CPU, and the CPU has the job of telling the GPU what tasks to process and complete. DCS: Black Shark also, AFAIK, is a single-thread program. It cannot allocate different tasks to different cores, this is why CPU affinity has the effect that it does. Were it a multi-thread program, the task of calculating, say, rotor physics could be assigned to core 0, while AI threads could be assigned to core 1. Since this is a single-thread program, all processes are assigned to a single core. CPU affinity decides what core that is assigned to. No matter what operating system, (except Windows 2000 and lower, operating systems which do not support hyperthreading) CPU affinity will have the same effect on performance. Just because it is on a DX10 supported operating system doesn't mean that physics calculations will be magically assigned to the GPU.

 

I have done my research, I do know what I am talking about. CPU affinity certainly has an effect in XP, as it does in Vista and Windows 7. No more of an effect in one than the other.

[Boulund]

I would like to say otherwise. My personal testing in XP and Win7 64bit show that there is indeed a difference in the efficiency of multicore handling on the two operating systems. My personal opinion on the matter is that on XP, different affinity settings did not improve, nor degrade performance in Black Shark. On Win7 on the other hand, setting affinity to two cores are most definitiely giving a boost to performance. This testing is of course unpublished and not saved anywhere else for any kind of validation =D.

 

You are though correct in your statements about the different direct X versions having no impact on this at all. The game runs a Dx9 engine and as such uses the same libraries on all operating systems, regardless if you're using Dx9, 10 or 11. I'm also of the opinion that this game is completely bottlenecked by CPU since pushing graphics settings over the top changes nothing extraordinary, but overclocking the CPU can majorly benefit performance.

Edited September 3, 2009 by Boulund

[slug88]

I would like to say otherwise. My personal testing in XP and Win7 64bit show that there is indeed a difference in the efficiency of multicore handling on the two operating systems. My personal opinion on the matter is that on XP, different affinity settings did not improve, nor degrade performance in Black Shark. On Win7 on the other hand, setting affinity to two cores are most definitiely giving a boost to performance. This testing is of course unpublished and not saved anywhere else for any kind of validation =D.

 

My own testing confirms this. I saw absolutely no benefit from changing affinity on XP.

[ZaltysZ]

In addition, DCS: Black Shark doesn't even use DX10. It doesn't matter what operating system, it doesn't use DX10, only DX9.0c.

 

DX10 is not important here. WDDM is important here. Advantages and disadvantages of this driver architecture affects both: DX10 and DX9. One of advantages is internal task scheduler, which makes use of multi core systems. That is why pretty big difference in FPS exists for XP and Vista/Win7 then game is run on multiple cores.

[nemises]

In what way is CPU affinity related to the allocation of limited tasks to the GPU related?

 

..

 

I have done my research, I do know what I am talking about. CPU affinity certainly has an effect in XP, as it does in Vista and Windows 7. No more of an effect in one than the other.

 

so, take a deep breath, and hop down off the horse for a second.

 

There has been literally dozens of threads , and probably over a hundred posts on this exact topic over the last 12 months..and the result?

Black Shark performance is NOT improved by setting muticore affinity in XP

However, it can have a considerable increase in performance on Vista and Win7

 

go test it yourself if you like.

[Guest]

I have done my research, I do know what I am talking about. CPU affinity certainly has an effect in XP, as it does in Vista and Windows 7. No more of an effect in one than the other.

 

I think maybe you are misinterpreting nemesis' (and others) point. No one is arguing that multiple cores do not help performance in XP generally. I think everyone agrees that, in general, more cores = better when using XP.

 

What we are saying is that when using Black Shark setting the affinity to more than one core has little or no effect on FPS. I wrote one of the original affinity setting tools for Black Shark, and in the process I ran and recorded literally hundreds of performance tests with various combinations of affinity settings in both XP and Vista (dual-boot). I can promise you that at least in Black Shark 1.0, there was no noticeable difference in FPS in XP when using multiple cores vs. using a single core. To date, I have heard very few people claim that setting affinity to multiple cores in XP provides any substantial FPS increase over a single core, and would certainly be interested (and surprised) if you can post performance data from your system that shows a big increase in XP.

 

In Vista, on the other hand, setting the affinity to multiple cores provided a very substantial FPS boost (25-40%) on my system, and many others.

Edited September 4, 2009 by wombat778