Here I use 2 pc’s.

8700K @ 5.0 / 16 Gb 3600 mhz  / 3090 / M2 /  1x 4K display

9740 @ 4.7 / 32 Gb 3200 mhz / 3090 / M2 / 2x 4K as one front view

After the latest update the 9740 pc shows about 10-15% lower fps than before. No big issue as at Schipho EHAM with lots of Live Traffic (AIG)  I can have 45 fps. With Vsync On and 30 hertz it is good.

However, after flying for 2 hours the fps has dropped till 26 which means 15 ( vsync / 2 ). And the ac is flying at 35000 ft with little clouds over the Mediterranean….

Wheh I make the view smaller so it fits on 1 screen the fps stays low. 

Anyone experienced this ?

https://www.dropbox.com/s/cfy2uzabpknnc8p/Foto 25-11-2021 19 45 20.jpg?dl=0

 

Edited November 25, 20214 yr by GSalden

Try turning traffic off, apply and save, then turn back on, apply and save. That helped my situation. 

All traffic is Off inside MSFS  I use PSXT Live Traffic.

But even with PSXT not running ( so no Live Traffic ) this occurs.

It's an old bug that's been around for a long time now, probably a memory leak

3 minutes ago, Ixoye said:

It's an old bug that's been around for a long time now, probably a memory leak

Indeed:

https://forums.flightsimulator.com/t/after-playing-a-few-hours-fps-drops-from-40-to-5fps/389603

 

27 minutes ago, RALF9636 said:

Indeed:

https://forums.flightsimulator.com/t/after-playing-a-few-hours-fps-drops-from-40-to-5fps/389603

 

But in my case low cpu usage, low RAM usage, low VRAM usage. But the fps drops. If there was a memory leak I would see that….

My cpu can go up to 4.7 but stays around 4.3 as there is little load on the cores ( see the link with screenshot in my first post ).

4 minutes ago, GSalden said:

But in my case low cpu usage, low RAM usage, low VRAM usage. But the fps drops. If there was a memory leak I would see that….

My cpu can go up to 4.7 but stays around 4.3 as there is little load on the cores ( see the link with screenshot in my first post ).

Can you do me a favor. When it does happen, can you enable the developer mode and select display fps. I am curious to see if you get the same issue have been reporting for a while The manipulator threads will go crazy and have a really high ms response.

17 minutes ago, GSalden said:

But in my case low cpu usage, low RAM usage, low VRAM usage. But the fps drops. If there was a memory leak I would see that….

My cpu can go up to 4.7 but stays around 4.3 as there is little load on the cores ( see the link with screenshot in my first post ).

Yes, that's what I see as well. I don't think it is a memory leak, must be something else. 

Nevertheless the issue exists for a while. It happens sporadically to me, mostly when flying in Europe. I haven't found a way to reproduce it or narrow down the possible cause. Seems Asobo hasn't either so far.

 

Making now a route from EBBR-ESSB with A32nx and i had also a weird frame drop ( from Denmark to Sweden) which stayed stable to 30s-40 fps. Usually i have over 60s on cruise conditions. I thought it was AI traffic ( AIG or AIGT) in the beginning  but after many tests i went back to go 60s by reducing terrain level of detail. 100% cpu main thread issue 

 

Made a complete flight from Amsterdam to Bodrum. See the fps after landing ! !

https://www.dropbox.com/s/kmlzonzmrrs2q4o/Foto 25-11-2021 12 34 54.jpg?dl=0

The Main thread is now 69.4 ms ….The manipulators are 59.8 ms ….

Fps just 14 ….
Load on the cores was low. Enough RAM, enough VRAM 

- - - 

To compare : here 10 min after startup at Amsterdam Schiphol. See the big difference:

https://www.dropbox.com/s/3rxbkcy8o3tzt0j/Foto 26-11-2021 07 40 20.jpg?dl=0

 

Edited November 26, 20214 yr by GSalden

10 hours ago, GSalden said:

low cpu usage

Across all cores it's low but if you open task manager you will see that one thread is maxed out. AI traffic is on the main thread and when you fly for a long time the poor single core has to deal with dozen of aircraft.

I bet that if you disable traffic completely the framerate returns to normal values.

It's the same old story, maybe FS2030 will use multithreading properly.

28 minutes ago, MrFuzzy said:

Across all cores it's low but if you open task manager you will see that one thread is maxed out. AI traffic is on the main thread and when you fly for a long time the poor single core has to deal with dozen of aircraft.

I bet that if you disable traffic completely the framerate returns to normal values.

It's the same old story, maybe FS2030 will use multithreading properly.

As you can see in my first screenshot none of the cores is maxed out….

What I do agree upon is that it might have to do with AI aircraft.

I just finished a test at Schiphol spotting AI aircraft. Within the 20 minutes I tested the framerate went done another 4 fps.

At this moment I am making the same 3h flight but without AI aircraft to see what will happen.

Will report back in this thread….

20 minutes ago, GSalden said:

As you can see in my first screenshot none of the cores is maxed out….

Yes, now I saw it... it was 83%. But it was also 300 MHz below the frequency of the others. Maybe it actually gets maxed out and throttles down to 4 GHz to avoid overheating? 

I don't understand how the CPU temperature can be 33 °C honestly 🙂  Are your sensors OK or it's picking up  the water temp sensor...?

Edited November 26, 20214 yr by MrFuzzy

1 hour ago, MrFuzzy said:

Yes, now I saw it... it was 83%. But it was also 300 MHz below the frequency of the others. Maybe it actually gets maxed out and throttles down to 4 GHz to avoid overheating? 

I don't understand how the CPU temperature can be 33 °C honestly 🙂  Are your sensors OK or it's picking up  the water temp sensor...?

My system is pull/pushed liquid cooled. Therefore the low core temps.

Just did another test. It was a 3h flight but after half an hour I set the sim to 2X speed and let it run for 45 minutes.

When I came back I saw a framerate drop to 19 fps ! At 35000 ft … No AI aircraft enabled this time.

https://www.dropbox.com/s/q0r77cgsphi3wwq/Foto 26-11-2021 11 07 50.jpg?dl=0
 

Later today I will do the same 3h flight only then at normal sim speed.

3 hours ago, GSalden said:

My system is pull/pushed liquid cooled. Therefore the low core temps.

Just did another test. It was a 3h flight but after half an hour I set the sim to 2X speed and let it run for 45 minutes.

When I came back I saw a framerate drop to 19 fps ! At 35000 ft … No AI aircraft enabled this time.

https://www.dropbox.com/s/q0r77cgsphi3wwq/Foto 26-11-2021 11 07 50.jpg?dl=0
 

Later today I will do the same 3h flight only then at normal sim speed.

Which is your terrain level of detail? I had the same fps drop during cruise ( after 1 hour of flight ) and only when i reduced tod from 200 to 100 i  brought back my usual  fps/performance.