OOM nightmare

[jzimmermann 238]

No the jobscheduler section won't be removed by P3D. With the 8 core HT enabled, 21760 gives four straight cores to the sim above the first four cores. On a 4GHz class CPU four cores only beats three by around 3-7%. More than four reduces performance and robs the CPU of throughput for other tasks.

 

Hi Steve,

 

Theoretically that sounds plausible, but in practice it just doesn't work. And if the only programs running are the OS, P3Dv3 and FS Global Real Weather, why leave half of the available cores just to run weather and the OS, giving P3Dv3 only 50% of the i7-5960X CPU's performance? To me that just doesn't make sense.

 

Cheers,

 

Jerome

[SteveW 1,792]

Hi Steve,

 

Theoretically that sounds plausible, but in practice it just doesn't work. And if the only programs running are the OS, P3Dv3 and FS Global Real Weather, why leave half of the available cores just to run weather and the OS, giving P3Dv3 only 50% of the i7-5960X CPU's performance? To me that just doesn't make sense.

 

Cheers,

 

Jerome

Unfortunately, that's just because you don't understand it.

[SteveW 1,792]

 

 

Some guys bothered to check it out. They found they could hardly improve performance going from three to four cores. Five made matters worse. Six, seven eight, made no difference. All that happens is these extra processes pull at the performance of the sim and occupy CPU space that is better served elsewhere.

[jzimmermann 238]

Unfortunately, that's just because you don't understand it.

 

Hi Steve,

 

Why the condescending remark?

 

And even if I didn't have as much technical knowledge as you're presuming, the fact that a setting of AffinityMask=21760 invokes terrible stutters speaks for itself.

 

Cheers,

 

Jerome

[SteveW 1,792]

I'm not being condescending, I can't hold everyone's hand with this subject, and you're not getting it.

Cheers!

 

Guy's. If four cores is not working, for you, then logically something is wrong with your setup. Why? Because hundreds of four core CPU's can't be wrong.

[asanal 32]

I have  AM=21760 and don't have any  stutters. I am flying  PMDG  777X . P3D v3.

CPU i7-5960X.

[SteveW 1,792]

Thanks Ahmet.

 

Apologies for perhaps being over assertive. I'm not being arrogant or condescending when I find I'm having to defend a well understood technical situation. The HT/AM stuff going round has made a buzz because it's actually working well for most. When it hasn't worked for some, it has been down to some other thing. There's a big neon error sign flashing over a system that can't run P3D on four cores, or that has to be set HT off to gain respectable performance.

 

If I remember correctly Ahmet's system already had a reasonable AM. But we tuned it a bit and I think saved a bit of heat, for no reduction in performance. Maybe gained 1-200Mb VAS too in the long run. Getting AMs right won't necessarily net us fps.

[Angelo Cosma 61]

Hey Steve, I am running a 6700K at 4.80Ghz, Turbo, Speedstep, and HT off. I do not have AF in my P3D.cfg Should I add one? If so is it still 14? Great info about offloading processes from core 0 on up. I have never done this and can't wait to try! Let me know, thanks buddy. 

[SteveW 1,792]

Hey Angelo, let's look at your system carefully. 4.8GHz could mean HT enabled increases temps too much irrespective of AM used. Since HT does a little more work on a core and produces a few % more heat. Keeping it HT Off to gain maximum GHz and full steam ahead main thread will work well with the four cores. I would leave the AM out of your cfg, and aim all addons above core zero. I always suggest using the .bat method to start exe addons, since starting an addon and then moving it with software or the Task Manager Set Affinity menu function may not work as intended. Keep in touch.

 

Four cores no AM same as AM=15=1111

 

Keep addon exe's to 1010 = Hex A, decimal 10

[asanal 32]

I disabled HT and gain 400Mb VAS? Is it OK ?  :Whew: Can it be harmful to my PC?

[swiesma 625]

I disabled HT and gain 400Mb VAS? Is it OK ?  :Whew: Can it be harmful to my PC?

 

Disabling HT will not harm your PC in any way  :smile:

You only lose 4 virtual cores. What this means performance wise depends on the software you are using.

[asanal 32]

Stefan, thanks for your reply.

My "HT ON" AM settings was 21760,it was given by Steve.

Now I want to test "HT OFF". I found  AM settings 254 for i7 5960X

 

Is it OK?