On 10/28/2021 at 1:53 PM, Rob_Ainscough said:

A stab in the dark, only because I happened to be testing something recently ... try this ...

Prepar3d.cfg

[Display]
SwapChainUseWaitableObject=0

Check the value (default is 0) ... if it's 0 then change to 1 ... if it's 1 then change to 0.

Vsync must be set to ON and frames = Unlimited.

VRR Off

Cheers, Rob.

Cheers Rob

I gave this a try, early indications are a big improvement, even in heavy cloud cover. I need to do some my flights to be sure though. How did you happen to stumble across that one 😄? Never heard of SwapChain UseWaitableObject settings before? 

I've added that and deleted shaders.. still running into a bottleneck on CPU0 from the looks of it. Total CPU usage is 20ish%, but the CPU0 core is totally maxed out at 100%. I guess time to try an affinity mask removing P3D from that core?

Edit: Negative - that unfortunately did not work. Still same behavior, stutters start about an hour after takeoff, get progressively worse until it's stuttering every 10-15 seconds. Taking the process off Core 0 actually made it worse. It doesn't appear P3D is distributing the load fairly across all processor cores, I have 24 cores in Process Manager, and Core 0 is at 100%, but the rest hover in the low 20s.

This is with:
Shaders deleted and regenerated
SwapChain tweak enabled
Same behavior with both AI traffic off and volumetric clouds off, and both of those enabled.

Edited October 30, 20214 yr by mspencer

@mspencer, have you tried my suggestion of trying a default aircraft?

Yes - same behavior regardless of aircraft. 

I think the key here may be an affinitymask setting. I juggled cores around in Process Manager, and taking it off Core0 was unusably poor performance - but once I put it back on Core0 it stopped freezing, and I noticed the sim had distributed the load across CPU cores a little better.

What resolution and refresh rate of your monitor? You said core 0 is maxed out meaning settings could be too high for your hardware.

For a test reduce Autogen and Scenery complexity down to minimum and report back.

Right, well that just couldn't be the problem, though. My settings are mid-tier at best. Everything is middle or low-end in the sliders. My system can easily hit the performance needed. We're not talking La Guardia or London, right now I'm getting frame by frame performance every 10 seconds flying into Khartoum, a desert with no scenery.

The problem is, it will max out Core0. If you do some process lassoing and get it off Core0, voila, doesn't break a sweat. No microstutters and it just glides along at the locked 30 frames without breaching 20% total CPU usage across all cores. I've used an affinity mask to try and distribute across all cores and it does not work. Could this be a fundamental issue with the Ryzen processor and P3D, or what could I do to hopefully improve the CPU usage policy of P3D? Right now it is simply not WAD.

 

Edit: Confirmed - moved everything in settings to the left. Still same issue.

Edited October 30, 20214 yr by mspencer

Take into account, that there are many other influencers on performance than just the CPU. It also depends how well does perform the memory lanes of your motherboard in conjunction with the SSD the RAM, CPU, etc. This has it´s own special science. 

Generally speaking P3D is capable in the use and balancing of Multithreaded CPU´s and this was even improved since V5 and DX12. I would not suggest the use of an affinity mask, because the latencity of the system depends on so many other components where AM has more or less a placebo effect. And you may block or disable just the internal performance optimasations. But i suggest to use the physicsl cores of the CPU only. Turn off multithreading and use just your 12 physical cores. The use of virtual cores consumes performance depending on the architecture of the procesdor and it´s layers, in simple words. 

Edited October 31, 20214 yr by BerndB

7 minutes ago, BerndB said:

would not suggest the use of an affinity mask, because the latencity of the system depends on so many other components where AM has more or less a placebo effect. And you may block or disable just the internal performance optimasations. But i suggest to use the physicsl cores of the CPU only. Turn off multithreading and use just your 12 physical cores.

I was very reluctant to change my BIOS on a professionally built PC but after taking advice from people with far more knowledge than me I did turn off Hyperthreading and I'm pleased with the results. I even detected a small fps boost when running a severe test at Heathrow with multiple Ai.

4 minutes ago, Ray Proudfoot said:

I was very reluctant to change my BIOS on a professionally built PC but after taking advice from people with far more knowledge than me I did turn off Hyperthreading and I'm pleased with the results. I even detected a small fps boost when running a severe test at Heathrow with multiple Ai.

yea, one reason is, that the overclocking works for all physical cores only with HT off. If HT is used only the 0 core gets the full speed overclocking and the others just a devide.

2 minutes ago, BerndB said:

yea, one reason is, that the overclocking works for all physical cores only with HT off. If HT is used only the 0 core gets the full speed overclocking and the others just a devide.

I installed ASUS AISUITE and ran the process. My first 3 cores were overclocked to 5.2 and the remaining 3 to 5.0.

In Windows 11 affinity cannot be used due how the Intel CPU works, so if you do go to 11 don`t use the same setting and tweaks you may find they no longer work.

Check you don`t have a program (not flight sim related) running in the background that`s making calls on the CPU or net connection, start the sim then open task manager in the foreground to check.  

Edited October 31, 20214 yr by G-RFRY

PROBLEM RESOLVED.

After many many attempts to fix this, it appears it must have been a ShadersHLSL issue. Client ripped out, deleted everyyy temp file I could find, and this behavior is completely gone. 

SwapChainUseWaitableObject=0 did not have any effect, positive or negative, for me. AffinityMask didn't solve it, I did clear out the P3D.cfg file as well but I couldn't find anything in there that could have caused such a drastic performance hit.

Not only that, the sim is performing better than it did before this issue showed up. I can't emphasize enough how helpful it is sometimes to reset and delete shaders, especially for those of us with heavily modded sims.

Now I can finally fly again 🙂

Glad you solved it!

Would you mind sharing each steps you have done? It maybe useful for others 🙂 

On 10/27/2021 at 10:53 PM, Rob_Ainscough said:

A stab in the dark, only because I happened to be testing something recently ... try this ...

Prepar3d.cfg

[Display]
SwapChainUseWaitableObject=0

Check the value (default is 0) ... if it's 0 then change to 1 ... if it's 1 then change to 0.

Vsync must be set to ON and frames = Unlimited.

VRR Off

Cheers, Rob.

Can you simply explain what this setting does?  I changed it from "0" to "1" but haven't noticed any difference yet.

I don't believe that an NDA would preclude you from describing what an existing P3D setting does.

Thanks.

Dave

 

On 11/6/2021 at 9:15 AM, mspencer said:

PROBLEM RESOLVED.

After many many attempts to fix this, it appears it must have been a ShadersHLSL issue. Client ripped out, deleted everyyy temp file I could find, and this behavior is completely gone. 

SwapChainUseWaitableObject=0 did not have any effect, positive or negative, for me. AffinityMask didn't solve it, I did clear out the P3D.cfg file as well but I couldn't find anything in there that could have caused such a drastic performance hit.

Not only that, the sim is performing better than it did before this issue showed up. I can't emphasize enough how helpful it is sometimes to reset and delete shaders, especially for those of us with heavily modded sims.

Now I can finally fly again 🙂

Could you please explain how you got it working with the ShaderHLSL since I am having the same problem as you did. It would be much appreciated!