Constantly Mainthread Limited Regardless of Settings

Since updating to SU6 my performance has decreased and I seem to be constantly mainthread limited.

I have:

i7 10700k
RTX 3080
32 GB Ram @ 3200
1TB SSD
1440p

Setting to default Ultra:

Settings to Low:

This is the same whether its the FBW 320 or default Caravan (no nxi). I have nothing in my copmmunity folder except FSUIPC and AAO

In practice i have found i get stutters and lack of smoothness on the ground and a drop in FPS after 30 mins in the air.

Before SU6 i just set ultra and never worried about it.

Any help, advice, discussion great;y appreciated.

That is odd. You have one thread maxed out, with the others at low utilization.

I don’t have the 10700K, but I do have the 10700 non-K and what I usually see is three threads very close to 100%, three threads at about 75%, and ten threads around 10%. This is on high settings, GTX 1080, 32GB RAM, NVMe install.

Maybe there is a BIOS or system setting limiting your core or thread assignments?

Mainthread means your CPU is at its limit. And you can see it is clearly the case, your last core is absolutely maxed out. This is always the case with MSFS, it utilises one core more than the others.
You can not do anything about it.

Also, it seems you are using Experimental version of the FBW. The latest updates had quite a bit of a performance impact and will cause more load on the CPU. They are working on improving this, i already asked yesterday.

What you can do right now, is limiting your frames to 30FPS. It will smooth things out and reducing the stress on your CPU.

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Second screenshot is in the green on the mainthread so don’t think that is an issue there, was another reflection option added in the setting have you played around with that?

Also in nvidia control panel is the threaded optimisation set to auto or on.
Also check the power management is set to max performance.

I see virtualisation is enabled have you tried disabling it in bios.

I knew it used only one thread more than others but is this corebeing maxed out normal.

I tried with the default Caravan thinking it was amybe the FBW Exp but and was still maxed out on that thread

My understanding is that the mainthread joins all the work of the other cores to send to gpu to be draw.

I think this is the case in all games just this sim is heavier on the cpu.

Second screenshot was at low settings.

Threaded optimisation is set to auto and power max performance set

By virtualisation do you mean hyper-threading?

I’ve set everything back to default in the bios…

yes. for now, it is.

I don’t think there’s anything wrong here at all. And getting >80 fps in the FBW is pretty incredible regardless of settings, to be honest.
Prior to SU5 I could be CPU limited to about 60 fps in the stock A320, less demanding than the FBW, at literally the lowest possible settings and at 720p.

Try HT off. You dont need 16 threads for msfs. This gives that core a little more headroom.

If i remember rightly its the hyper-v setting in the bios. Is said to increase cpu load but can’t say i have bothered to see if it makes any difference or not. But might be worth trying it to see.

Good to hear that this normal. Its more the increase in stuttering since SU6 that is getting my attention, wasn’t sure if this MainThread being maxed out was the cause as I keep reading different things

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I too had reduced performance had to lower a few settings, some of them don’t need to be on ultra anyway.

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as said, these small stutters that appear, are also caused by the FBW is you have the latest updates installed. i get them too.

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I see the same. in SU5 I never worried about it, was butter smooth at all times.

In SU6 my mainthread is hammered, even in lower settings. Not bad enough to cause stutters constantly, but definitely more sensitive than before. With terrain LOD set to the usual 200 it gets a little better, I can usually maintain 60fps with some drops, but at 400 I’m hovering around 45-55 with some stutters.

i9 9900K@5GHz
3080Ti
32Mb 3600MHz RAM

@atledreier Have you increased terrain caching to Ultra? If so, that’s most likely the cause of the increased CPU usage. SU5 used “medium” as a locked setting, which will reduce CPU usage by not loading full-quality scenery all along the plane.
Going down to medium will probably improve your average framerate, but increase stutters while panning. Sadly there’s no way to get it perfect at both times; for me, the closest thing to perfect is caching Ultra and LOD 200.

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Here is my 10700 utilization from another thread for comparison:

Hi there are a couple of other threads regarding stuttering whilst on the ground, both inside and outside the cockpit (all aircraft). This is since SU6. I have had to lower terrain level of detail from 200 to 125 in order to smooth things out for now.

Good to know thanks