CPUs with P-Cores and E-Cores - Task affinity

Hey all! Asking all the guys with CPUs with P-Cores and E-Cores.

I’m thinking of assigning all the accessory tasks I run together with FS2020 to the E-Cores (threads).

In my case, I would have:

FS2020 + Windows Mixed Reality (I have a G2) - Free to use whatever cores they want
LittleNavMap/FlyLiveStudio/Sim Racing Studio/Sim Shaker/Ebag/OBS - E-Cores (threads) only.

So I’d have the first 8 Performance cores (16 threads) reserved for FS2020, and the other 16 Efficiency cores (16 threads) for all the other stuff.

Do you think this plan could free up as much CPU power as possible for the simulator?

I do this now using process lasso and it works no problem….I haven’t done formal testing with lasso on and then off, but I can see that the workload is more evenly spread out across the entire cpu so I do think it helps avoid any one of the p-cores running the sim. I may do formal testing but it would require using cap frame ex which is a great tool to capture frame times, 0.1% lows, etc in a data driven way to compare results in a controlled flight plan. I first used lasso to force my varjo headset software to run on p-cores along with MSFS as that seemed to eliminate some micro stuttering and I put many other tasks on e cores only (hardware monitoring, navigraph, etc).

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Thanks! That’s exactly what I want to do - only without Lasso, but with a series of .bat files :slight_smile:

Anyway, how’s Lasso? I know it can set also priorities and so on, do you recommend it?

really good bit of kit… I use Process Lasso Pro https://bitsum.com

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Doing exactly that for a long time and I noticed an improved sim experience. Difficult to measure, but as a tech guy watching the processes distribute over the cores as they do now, this cannot do any harm and will improve things.

But important to keep MSFS free from restrictions, otherwise you will see issues.

I can really recommend it. But it is important to not over-regulate things, which can happen quickly. This notice is even written into the documentation.

Do basic tuning and let the windows 11 core scheduler do its job.

Thanks. So MSFS must remain free to use all the cores. I was wondering… my 13900kf has 2 cores with 6 GHz boost, and the others @ 5,5 GHz… is there any way to use these two cores as “main ones” for the sim?

And also about priority… Does it help? I saw a note (I installed Lasso) that suggests not to use Real Time, for example.

Those two cores will downclock to 5.5 when all 8 cores have some load, so there is no need to assign those cores. You can try to assign MSFS priority to High, but when it is using those 8 p-cores nearly exclusively, the priority will not have any effect.

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I have an i5 13600k. All P-cores are running at 5.3 Ghz and all E-cores at 4.2 ghz all the time. With Lasso prozess I have disabled all E-cores solely for MSFS, So all P cores are used for the sim. All E cores are used i.e for every fenix applications and so, all P cores are disabled for all fenix applications. This gives me the smoothest flight expirience. The core management by windows is not very good. Before I tweaked that, windows was running msfs all the way on my E-cores what gave me stutter, so I had to manage it by myself.

Windows 10 or Windows 11? As far as I heard, the task scheduler of Windows 11 is capable of using those P- and E-cores more correctly than the one of Windows 10. I just updated to Windows 11 this weekend and I see no real improvement (but also no worsening). Might still use the Process Lasso in the future if you report such good results here.

BTW: you obviously overclocked your 13600K. Does this little overclock of only 4% and 7% resp. really do anything besides increasing power consumption and heat generation?