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LuftWulf190
06-27-2007, 01:24 AM
OK what exactly does this do? Some one in HL said that this would make IL2 run on both cores, which doesn't make sense. The Il2 engine I though could not run on both cores on a dual core system, so what does this cfg.ini entry mean?

LuftWulf190
06-27-2007, 01:24 AM
OK what exactly does this do? Some one in HL said that this would make IL2 run on both cores, which doesn't make sense. The Il2 engine I though could not run on both cores on a dual core system, so what does this cfg.ini entry mean?

DmdSeeker
06-27-2007, 02:55 AM
It does what you think it does, it forces IL-2 to use the designated number of cores on a multi core system.

You'll notice it's remmed (disabled) by default.

I've not played with it, and I've heard very mixed reviews from those that have.

I suspect it's one of those settings where only really rigorous and exact testing would show it's effect, it's not like jumping screen resolutions where the effect is readily apparent; and furthermore, I'd imagine the operating system (Win 9x, Win NT5, Win NT5x64 etc) would make a huge difference to the effect of the setting.

R_Target
06-27-2007, 05:29 AM
Do a search at SimHQ. Someone tested it and found little difference.

BBB_Hyperion
06-27-2007, 05:32 AM
You can select 1 cpu exclusively so difference is there when other cpu is loaded.

LuftWulf190
06-27-2007, 03:24 PM
I found little or no difference when I enabled and tried settings, 1, 2, and 3. Setting three was pretty mcuh the same reason I usally get on my Opty 170, both cores, usally the second, working more then the other.

When I tried setting 1 and 2, it just switched all the processes to either of the cores.

In the end I didn't find anything to really nessiate useing it, so I just disabled it.

striker-85
06-28-2007, 11:14 AM
For me the point of ProcessAffinityMask is so I can run the game on it's own dedicated core and run everything else on the other core, which gives you greater performance in game.


The ProcessAffinityMask is a bitmask with the following values for Dual Core systems:

0 - Balance the load across core0 and core1
1 - use core0 exclusively
2 - use core1 exclusively
3 - Balance the load across core0 and core1

One thing I see posted alot is that setting the value to 0 or 3 will use ALL CPUs but that is a bit of a misnomer. The Il-2 game code is a single thread and setting the value to 0 or 3 simply means you don't care which core it runs on, the OS will choose a core to run the thread on based on load. It will not run the game thread on both cores simultaneously but will bounce between cores essentially using 50% of each core.

On my system I set ProcessAffinityMask=2 so IL-2 runs exclusively on core1. I then use prioaff.exe (a program obtained on the Internet) to set all of my other programs to core0. You could manually set each program to use core0 using Task Manager, but this becomes tedious after each reboot. With prioaff.exe I modified my Registry so all of my autorun programs are set to use core0. I also modified my shortcuts on commonly used programs with prioaff.exe so they will use core0. This way I have core1 reserved exclusively for Il-2.

I noticed a definite improvement in fps running this way, the biggest increase was when I have TIR running on core0. Before when I just left it up to chance I noticed degraded performance when TIR and Il-2 used the same core.

Here is a link to a small config guide for optimizing IL-2 for multi-core CPUs. It wasn't quite ready to be published yet, it is still ugly and may contain spelling errors but the info and steps are all OK.

http://il2.netteq.com/Muliti-Core_Guide.aspx

I saw a 20 -30 fps increase, primarily when I moved TrackIR to core0 only. Your mileage may vary.


I posted more detail in this thread as well as info for settings on Quad core CPUs.

http://forums.ubi.com/eve/forums/a/tpc/f/49310655/m/2531042843/p/28

R_Target
06-29-2007, 08:34 PM
Striker, thanks for the tips. I had been manually putting TIR and all processes I could on Core 0 and IL2 on Core 1 with the Task Manager, but this looks much better. http://forums.ubi.com/images/smilies/25.gif