glider_uk

Are you getting even usage across all Cores?

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Title asks the question as I am not.

X5960 OC'd to 4Ghz. HT on so 16 cores.
CPU 0 100% CPU 1 25% all the rest negligible usage.

Just curious what anybody else is getting?

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My 5820k @4.5 has all cores nearly at 100% only core 1 is about 75 %

I need more cores ;-)

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Nope. There is some trick with task manager to uncheck the affinity for CPU 0, then re-enable it and it's supposedly evens the core usage. Whatever that means ultimately for the sim, I don't know.

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Also on a 5960x @ 4.375GHz. Seeing pretty heavy usage on 15 threads. Core 0 sees almost constant 95%+ usage due to it being the main thread for the sim. The rest of the cores work pretty heavily to render the terrain. Core 1 doesn't see much usage, as it's the logical of 0 and the main thread doesn't multi-thread. Also discovered my game becomes smoother when I remove Core 1 completely for the P3D.exe.

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I loved to know how to clock that high, no good at that, My GPU is only running at Max 30%.
 

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12 minutes ago, glider_uk said:

I loved to know how to clock that high, no good at that, My GPU is only running at Max 30%.
 

It's actually on the low side for the 5960x, as I'm staying around 1.3 volt. It's not recommended to go over 1.3 with these for daily usage.

But it takes a bit of messing around. Using my ram's 3000 Mhz XMP, which enables a BCLK of 125. Ratio at 35 and then play with offset voltage, as manual voltage kills power saving features and auto voltage just applies way too much. Run a few stress tests and you're golden. 

Yes, I know, easier said than done.

EDIT: Here's a quick snap of my CPU usage in the air

B4XvvHD.jpg

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It's somewhat difficult for me to understand how to answer the question as phrased. First, I think to test CPU "evenness", one should put all the IQ settings to the max, such that both the CPU and GPU are stressed heavily. When I do so with my i7-6700 (OCed to 4.4)/GTX 1080 setup, I get :

1. HT on: CPU 0 95-100%, CPU 1 25-30% and the remaining 6 logical cores 80-100%. My GPU is generally at 90-100%.

2. HT off: all 4 physical cores 50-100% (which appears to be related to scenery loading as the aircraft moves across the landscape), GPU 90-100%.

This includes all presently available ORBX add-ons, ASP4/ASCA, My T 6 (40%/15%) and TrackIR.

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27 minutes ago, AviatorMoser said:

Nope. There is some trick with task manager to uncheck the affinity for CPU 0, then re-enable it and it's supposedly evens the core usage. Whatever that means ultimately for the sim, I don't know.

That did the trick, it hasn't increased my FPS much but the load seems more spread

9 minutes ago, Sethos1988 said:

It's actually on the low side for the 5960x, as I'm staying around 1.3 volt. It's not recommended to go over 1.3 with these for daily usage.

But it takes a bit of messing around. Using my ram's 3000 Mhz XMP, which enables a BCLK of 125. Ratio at 35 and then play with offset voltage, as manual voltage kills power saving features and auto voltage just applies way too much. Run a few stress tests and you're golden. 

Yes, I know, easier said than done.

Erm Yeah ok. I should really look into this, I paid for a watercooled processor on a Asus Rampage extreme and never really took the time to investigate it.

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We don't expect to see even use of all "cores" since that's not how it works. Also the nomenclature is confusing, when HT is enabled we should think in terms of logical processors (LPs). That's because each core has two LPs - with HT enabled they share throughput of that core. So for example when we see both HT LPs of the same core at 100% each, they are in fact only at 50% of core throughput.

But then with P3D we have one monolithic process for the UI and Scene rendering, and several others also monolithic, but these others don't max out unless scene loading, they may well only be at 30%.

It's best to give the main process a whole core by enabling only one LP of the first core we want to allocate with the Affinity Mask in the Prepar3D.cfg jobsheduler section.

We understand this first sim process requires maximum throughput, the same bandwidth can be given to the other processes of the sim by allocating one LP from each of the other cores. We would like to give the first two processes maximum throughput of our available cores, but we can allocate two LPs of each core after the second process which can optimise use of those cores and utilise the efficiency of HT at the same time. With eight cores we need not bother, worth testing though.

The sim processes split out over four LPs to produce the leanest first process. We can add LPs, when we do the sim splits out the scenery loading processes to improve the scenery loading speed (up to a point)

So with the eight core +HT CPU we can use an Affinity Mask (AM) = 00,00,01,01,01,01,00,00=1360 this allows the sim to slit over 4 processes one LP of each of four cores. We can add a couple of LPs to split the loading over 6 cores with 00,01,01,01,01,01,01,00=5460. Leaving cores free allows the jobscheduler to target those cores with new work rather than interrupt the flow of the sim cores. When no AM is used then inevitably, since each core has a process of the sim running, the sim will be interrupted by new work and does not leverage the fact we have many cores to split the work over more intelligently. Use a batch file to restrict affinity of exe apps to those cores unused by the sim.

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...finally - even though we use an AM, this only controls the LPs used by the sim. Even so at some stage the jobsheduler may possibly target new work at the spare LPs of the cores used by the sim. This happens irrespective of HT enabled or not, but when HT is enabled, at least the time taken switching processes on those cores is considerably reduced. Apps that control their own affinity setting usually work in this monolithic way - FSX and P3D are very similar.

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2 minutes ago, SteveW said:

...finally - even though we use an AM, this only controls the LPs used by the sim. Even so at some stage the jobsheduler may possibly target new work at the spare LPs of the cores used by the sim. This happens irrespective of HT enabled or not, but when HT is enabled, at least the time taken switching processes on those cores is considerably reduced. Apps that control their own affinity setting usually work in this monolithic way - FSX and P3D are very similar.

In fsx I could set affinity mask. In p3dv4 if I set affinity mask my scenery all around is very blurry. Am I doing something incorrect?

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15 minutes ago, SteveW said:

So with the eight core +HT CPU we can use an Affinity Mask (AM) = 00,00,01,01,01,01,00,00=1360

Hi Steve,

I have an i7 4790K with HT (hyper threading) ENABLED. In order to give the main process a whole core by enabling only one LP of the first core, as you mention above, what do you recommend?

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WIth TEXTURE_SIZE_EXP = 10, with lower, it goes little bit down

 

p3dv4_usage.png

 

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3 hours ago, MikeT707 said:

Hi Steve,

I have an i7 4790K with HT (hyper threading) ENABLED. In order to give the main process a whole core by enabling only one LP of the first core, as you mention above, what do you recommend?

I'm using 253, but, each system is different, so play with it little and will see what works for you.

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No, v4 has still no multicore support, neither HT support. The load balance you see come from the OS itsself who handles the CPU load. v4 supports only single Core.

And dont use AffinityMask, it will blurr all textures as soon they needs reloaded and autogen gets not generated anymore.

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