P3Dv3 Hyperthreading ON/OFF

[Martyson]

With P3Dv3 and Nvidia card supoort of DX12 is it best to have Hyperthreading ON or OFF?

[Saul]

Hi Vaughan,

In my system I found HT was better off. Basically with HT off I had the benefit of using around 500MB less per the exact same scenario and setting and also a performance increase of around 20%. I told Adam and the team are investigating. Rob has also done some tests with very similar results.

Hope that helps you out. I'm not sure what you mean by a DX12 system as I'm sure you know already that P3D uses DX11.

[nemo06]

This official reply from LM is very interesting.
I'll try, thanks Saul.

[Martyson]

Saul,

Thanks for the information.

I will get Hyper-threading turned off.

Note:
I just mentioned my Nvidia card supported Microsoft DirectX12 .. I did not know if that made a difference for Hyperthreading or not.

[Saul]

Just as a side Note. I'd make a comparison flight and monitor your FPS and VAS then turn off your HT and load up the same save scenario so you can see if your system is better with HT on or off ;)

I'm not sure but this maybe processor specific or limited to some CPU's. Its best to check for yourself.

[Patrice_p3d]

Personnally, when I deactivate HT, it seems that terrain texture are less frequently updated (i e terrain is more blurred). I have an intel core i7-4790k processor. So in my case, I let all cores active with HT when I use P3D. I use France VFR regional sceneries with lots of objects and autogen trees and buildings
Patrice

[Martyson]

Just as a side Note. I'd make a comparison flight and monitor your FPS and VAS then turn off your HT and load up the same save scenario so you can see if your system is better with HT on or off ;)

I'm not sure but this maybe processor specific or limited to some CPU's. Its best to check for yourself.

****
I turned off HyperThreading prior to reading your additional information.

I had not run any tests with HT ON but all seemed quite nice.

I am still loading software into a new PC ..
Just downloaded FlyTampa's Hong Kong Kai Tak (VHHX) and St Maartin Complete (TNCM) .. both for P3Dv3 now!

My CPU is i7-6700k 4GHz with Win7-64 16GB DDR4, Nvidia GT960 4GB, Audigy SE Soundblaster.


Maybe someone has already tested this combo with HT ON / OFF ??

[Fractal]

Hello ,

Is HT off recommended for p3dv3.1 or was that just for 3.0 ?

Regards

Karim

[Airwolf]

Hi Vaughan,

In my system I found HT was better off. Basically with HT off I had the benefit of using around 500MB less per the exact same scenario and setting and also a performance increase of around 20%. I told Adam and the team are investigating. Rob has also done some tests with very similar results.

Hope that helps you out. I'm not sure what you mean by a DX12 system as I'm sure you know already that P3D uses DX11.

Happy new Year 2016 Everyone,

With all the Hyperthreading On/Off; I guess I will share my results also. I have a i7-5820K (6 Core cpu). Yes with all the cores enabled -- there is a huge VAS hit.

I then disabled HT off in the bios, and just running the Sim with 4 cores (Cores 1, 2,3, 4). I let Core 0 and Core 5 be free by using affinity mask set to 30 in the prepar3d.cfg

Now here is the Kicker part of the story (especially for people who are seeing terrain textures being slowly rendered) - I do see that my Core 2 for example is running but at lower task activity vs Core 1, 3 and 4. I was like why is this core low performing.

And then I did this simple trick. I open up Task Manager in Windows 10 and go to Prepar3d, right click on affinity and let the menu show up. I do NOT change anything and just hit ok to the window which shows that I can enable Core 0 and Core 5 if I wanted to. I do NOT enable any other core as VAS spike will happen. Just click on "oK" and viola the Core 2 is now running on full power. And the lowly rendered frames are gone.

These are very weird and bizarre issues.

Hope this info helps.

Thanks,

Airwolf

[Wills]

Oh Wow... Thanks for sharing this. I've just tried the same thing as you explained and am also seeing the second core being fully utilised now after closing the affinity dialog without making any changes. I can't tell if it's actually made any different in the smoothness of the sim however.

This is super weird.

[Simu67]

Just as a side Note. I'd make a comparison flight and monitor your FPS and VAS then turn off your HT and load up the same save scenario so you can see if your system is better with HT on or off ;)

I'm not sure but this maybe processor specific or limited to some CPU's. Its best to check for yourself.

Has anybody tried if this is same in 3.2 ?

[BG2518]

If you have it OFF then put it back ON.

The OFF setting crucifies the PC in other areas I am finding and especially in Win 10.

e.g. almost instant large calcs on some of my complex spreadsheets are taking visible time to evaluate.

The PC is obviously more "snappy" when HT is ON.

Windows is the base platform to which P3D is the 3rd-party app so come on LM as MS won't talk to me about P3D performance.

Sorry, but I find this so funny.

BG2518-Bob.