[REPORTED]FPS sometimes hit hard while in a F/A-18 C

[Deano87]

Guys. Thanks for the input but this thread isn’t about how the static hornets effect FPS, it’s a well known issue with lots of static new hornets on screen your FPS dies. If you read the original post in this thread you can see it’s about a inexplicable massive drop in FPS when landing after a flight with No other aircraft on screen.

[Tepnox]

Hi there. I was investigating this kind of trouble you run into. I couldn't figure, how there was no real bottlenecking but also lacking performance after landing.

 

Reason for this is possibly a bug in the rendering engine of DCS World itself with the LUA CPU Usage value. Normally, this value hovers around 1-5 % when starting the mission (on ground and air) and just flying around. But after landing, the value for LUA CPU Usage spikes depending on the flying module up to 40% (on the F-18 for example) and it stays this way!

 

I made a video, it shows the F-18 starting on an empty NTTR-Map on the runway with a short round and landing. What you will see is, after landing on the runway, the LUA CPU Usage Value gets to around 40% in the Hornet. The load on the GPU drops significantly and thereby the FPS. There is no bottlenecking at all (not CPU not GPU wise).

 

For this test setting, all shadows are disabled (because they seem to have also a negative impact on the engine calculation and degrading the GPU loadout - especially the case, the more static airplanes are parked around you).

 

I locked the FPS with Rivatuner to 120fps and normally, this is the way, I like to fly around.

 

Watch for yourself:

 

For best viewing results, please use the 1440p quality for this video. (The text is very small in the analysis window).

 

The worst thing is, the LUA CPU Usage stays at this 40% after landing. Even switching to the F-5 and back to an unpowered F-18 doesn't help. To fix this back to normal, you have to leave the mission and load it up again.

 

I think, most people are not aware of this bug, because of gaming around 60fps. As you can see in the end, the FPS are barely around this value so many people wont notice the background high-load at all.

 

This is clearly an issue for people trying to fly in VR and for people who want to fly in much smoother high FPS.

 

Hope, this helps you out and gives a little more insight of what seems to be the problem. This is clearly reproduceable.

 

You can see, there is clearly something off, when watching the frametime line (values in ms - milliseconds). The frametime gives an impression of how fluid the frames are delivered. In the beginning, it is nearly flat with some minor spikes, because the GPU hits the limit and sometimes couldn't deliver 120fps but that is ok, as long as the load of the GPU is around 99%. The ideal way to play games in general, is to bottlenecking the GPU (load should be mostly around 99% so the GPU pushes the maximum available frames) - the CPU should always have some headroom and no usage around 99%. But having low CPU-usage AND low GPU-usage with lowered frames is always a bad sign as you can see in the frametime line after landing. You could see, that the engine is struggling hard in the backround and fighting itself for some reason.

Edited May 2, 2019 by Tepnox
typo

[Svsmokey]

I have been seeing the much-reduced frames at Kholki that many have discussed , both in the air and on the ground . Like many , i ascribed it to all the static aircraft there .

 

So i was surprised to see , having turned on the frame monitor , the same behavior at Kobeleti , with only 3 static aircraft , and again , in the air over the airfield as well as on the ground .

[Deano87]

Hi there. I was investigating this kind of trouble you run into. I couldn't figure, how there was no real bottlenecking but also lacking performance after landing.

 

Reason for this is possibly a bug in the rendering engine of DCS World itself with the LUA CPU Usage value. Normally, this value hovers around 1-5 % when starting the mission (on ground and air) and just flying around. But after landing, the value for LUA CPU Usage spikes depending on the flying module up to 40% (on the F-18 for example) and it stays this way!

 

I made a video, it shows the F-18 starting on an empty NTTR-Map on the runway with a short round and landing. What you will see is, after landing on the runway, the LUA CPU Usage Value gets to around 40% in the Hornet. The load on the GPU drops significantly and thereby the FPS. There is no bottlenecking at all (not CPU not GPU wise).

 

For this test setting, all shadows are disabled (because they seem to have also a negative impact on the engine calculation and degrading the GPU loadout - especially the case, the more static airplanes are parked around you).

 

I locked the FPS with Rivatuner to 120fps and normally, this is the way, I like to fly around.

 

Watch for yourself:

 

For best viewing results, please use the 1440p quality for this video. (The text is very small in the analysis window).

 

The worst thing is, the LUA CPU Usage stays at this 40% after landing. Even switching to the F-5 and back to an unpowered F-18 doesn't help. To fix this back to normal, you have to leave the mission and load it up again.

 

I think, most people are not aware of this bug, because of gaming around 60fps. As you can see in the end, the FPS are barely around this value so many people wont notice the background high-load at all.

 

This is clearly an issue for people trying to fly in VR and for people who want to fly in much smoother high FPS.

 

Hope, this helps you out and gives a little more insight of what seems to be the problem. This is clearly reproduceable.

 

You can see, there is clearly something off, when watching the frametime line (values in ms - milliseconds). The frametime gives an impression of how fluid the frames are delivered. In the beginning, it is nearly flat with some minor spikes, because the GPU hits the limit and sometimes couldn't deliver 120fps but that is ok, as long as the load of the GPU is around 99%. The ideal way to play games in general, is to bottlenecking the GPU (load should be mostly around 99% so the GPU pushes the maximum available frames) - the CPU should always have some headroom and no usage around 99%. But having low CPU-usage AND low GPU-usage with lowered frames is always a bad sign as you can see in the frametime line after landing. You could see, that the engine is struggling hard in the backround and fighting itself for some reason.

 

Amazing find! That’s really interesting. I hope maybe we can get a dev in here to check out your video.

[Tepnox]

Ok. Got some new testing. It is possible to reproduce this bug just by start and stopping on the runway.

 

I tested this with the F/A-18 on the runway. Accelerated to about 100 knots and came to a full stop. Repeated this step and every time, the load of the GPU shrinks and so do the FPS. This is because of the increasing LUA CPU value.

 

It took me 7 start-stop attempts to bring the performance down to 30 FPS and the LUA CPU Value was at a 70% level. This is the maximum, the performance will drop.

 

Tested this on the F-5. Same issue, but the performance drops were a little bit lower, so it took some more start-stop attempts to melt down the FPS.

 

Here is the video:

 

These were the ingame settings I used:

 

The extreme after 7 to 8 attempts looks like this:

 

FPS are down to 30 FPS, my GPU load only is at 24% and the LUA CPU Value is at 70%. Performance drops no further after these attempts.

 

So, clearly a bug in the engine itself it seems.

Edited May 3, 2019 by Tepnox

[Deano87]

Very interesting! I’ve PMed Nineline to try and get him to take a look at this thread.

[Mustang]

@Tepnox have you tried left alt+enter to enter true fullscreen mode?

[BuzzU]

Since the Hornet is a new plane. How does the F-14 compare to it? Anybody tested it?

[FalconPlot16]

there is really something wrong with optimization having weird drops too like constant 40 fps from 70's..

[NineLine]

Can you give me a track of this, just a short one of you speeding up then coming to a full stop? Make sure it happens for you, and I will run that. Let me know also what version the track was done in. I have not been able to reproduce this as of yet.

 

Ok. Got some new testing. It is possible to reproduce this bug just by start and stopping on the runway.

 

I tested this with the F/A-18 on the runway. Accelerated to about 100 knots and came to a full stop. Repeated this step and every time, the load of the GPU shrinks and so do the FPS. This is because of the increasing LUA CPU value.

 

It took me 7 start-stop attempts to bring the performance down to 30 FPS and the LUA CPU Value was at a 70% level. This is the maximum, the performance will drop.

 

Tested this on the F-5. Same issue, but the performance drops were a little bit lower, so it took some more start-stop attempts to melt down the FPS.

 

[toutenglisse]

I have I think this same bug - since several monthes - bug it works differently to me. It must be system dependant.

 

This bug happens to me when I come back to base to rearm - I just land, go to taxi and 180° turn in taxiway just to rearm not on the runway. At this moment usage (gpu+cpu) decrease and fps decrease by about half of my normal fps objective (45 fps VR). (it doesn't implies statics hornets)

 

But in my case it doesn't imply Lua cpu usage, that keeps below 1%.

 

I tried, to make a short track, just to take off / jettison / and land for rearm but then the bug doesn't happen. I have to fly/conduct my mission and then it happens when back to base.

Bug happens consistantly in the way I describe, nttr or caucasus.

 

Here 2 tracks (long one the bug happening - Always if I do the same / short one bug doesn't happen) and 2 Msi afterburner monitoring (1 with the bug showing in long track / 2nd no bug in short track).

 

Pecularity of the mission ? : it implies a radio script (it's infinite CAS/CAP nttr or caucasus east/west) but I don't think it matters, and in other missions where needed to rearm (f.e GlynLewis's missions) it happens also.

[Tepnox]

Can you give me a track of this, just a short one of you speeding up then coming to a full stop? Make sure it happens for you, and I will run that. Let me know also what version the track was done in. I have not been able to reproduce this as of yet.

 

There you go. I recorded this on OpenBeta 2.5.4.30386.

 

The LUA-CPU-Value is at 40% at the end of the track and my FPS drop is about 50 %. The CPU-load is identical, the GPU-load dropped from 99% to 50%. See my system specs in my signature.

 

I tested this track also on a Ryzen 2600X system (3000Mhz DDR4 and the same GTX1070Ti graphics card), the LUA-CPU-Value did not climb on that system - however, the FPS were dropping the same way.

FPS-Bug.trk

[NineLine]

Still unable to reproduce.

[SoloWingX]

Significant performance drop after landing - but only with the Hornet

 

Hello. I have this strange problem that I will describe momentarily... My basic PC specifications are: Ryzen 5 2600, GTX 1060 6GB, 16GB RAM.

 

Basically landing the Hornet at an airbase causes a significant performance drop (compared to airfield or air start). In my case the FPS from stable 60+ goes to the 30-40s. If I take off afterwards (from the airfield I just landed at causing my FPS to drop), the FPS is still affected in the air, especially when looking at the airfield I landed at previously.

 

This might sound complicated, so I present you my testing without FPS limiting... Might be interesting if somebody could reproduce it.

 

In ME, the only unit is my aircraft...

 

I load at Creech AFB in the Hornet. ~80FPS is average. I take off, ~90FPS in average. I land, everything OK, but FPS is decreasing as I am losing speed. As I look at the most populated area while stationary the FPS goes as low as 35FPS, ~40-50FPS when looking forward at almost empty landscape. After taking off the framerate gets better, but if I look at the airfield, it drops back to 35FPS.

 

I load the Tomcat. FPS is around ~10 lower compared to the Hornet, so ~70 while on ground. After I land the FPS is consistent with the starting FPS, ~65FPS when looking at the most populated areas.

 

Then I loaded the Hornet airborne, just before the runway on final. FPS goes down again, from ~80-90FPS to ~40FPS after landing. I load the Warthog in the same configuration, FPS is above 100 in the air and around 80-90FPS after landing when looking at the most populated areas.

 

Something is up with the Hornet... The same thing happens at most airfields as far as I can tell.

[doldi1989web.de]

+1

[SoloWingX]

I also noticed this problem, with the F/A-18C only. Yesterday I did some testing.

My basic PC specifications are: Ryzen 5 2600, GTX 1060 6GB, 16GB RAM @ 1080p.

 

In ME, the only unit on the map is my aircraft...

 

I load at Creech AFB in the Hornet. ~80FPS is average. I take off, ~90FPS in average. I land, everything OK, but FPS is decreasing as I am losing speed. As I look at the most populated area while stationary the FPS goes as low as 35FPS, ~40-50FPS when looking forward at almost empty landscape. After taking off the framerate gets better, but if I look at the airfield, it drops back to 35FPS.

 

I load the Tomcat. FPS is around ~10 lower compared to the Hornet, so ~70 while on ground. After I land the FPS is consistent with the starting FPS, ~65FPS when looking at the most populated areas.

 

Then I loaded the Hornet airborne, just before the runway on final. FPS goes down again, from ~80-90FPS to ~40FPS after landing. I load the Warthog in the same configuration, FPS is above 100 in the air and around 80-90FPS after landing when looking at the most populated areas.

 

The same thing happens at most airfields as far as I can tell. Before taking off and taxiing the performance is good, after landing the performance is bad. So I wouldn't say it's a shadow issue. Strange, strange...

[Deano87]

+999

 

I reported this many moons ago, and the thread got moved to the core sim "performance problems" section even though it is F-18 only issue. :doh:

 

Can confirm I still see this issue, with both Release and Open Beta and across multiple different systems/installs.

 

https://forums.eagle.ru/showthread.php?p=4006170#post4006170

[SoloWingX]

+999

 

I reported this many moons ago, and the thread got moved to the core sim "performance problems" section even though it is F-18 only issue. :doh:

 

Can confirm I still see this issue, with both Release and Open Beta and across multiple different systems/installs.

 

https://forums.eagle.ru/showthread.php?p=4006170#post4006170

 

Yeah, I found that thread today and posted there as well. If anything it got bumped at least.

[Deano87]

Yeah, I found that thread today and posted there as well. If anything it got bumped at least.

 

Yeah, I noticed! Thanks for the input!

[BIGNEWY]

Threads merged

 

I am not seeing this myself, frames seem normal for me.

 

Can you attach your options.lua it maybe specific to a particular setting

[Deano87]

Threads merged

 

I am not seeing this myself, frames seem normal for me.

 

Can you attach your options.lua it maybe specific to a particular setting

 

Thanks BIGNEWY, Any chance of moving this back to the Hornet bug forum? As it is an issue only with the Hornet and no other module.

 

I'll attach my options.lua later after work.

[BIGNEWY]

It is better in game performance, the title makes it clear it is a hornet problem so don't worry about that.

 

No rush on the options, when you are ready. I have had a play around with mine and see a slight drop but nothing I would be worried about, especially if you are getting 100+ anyway :)

[Deano87]

.. a slight drop but nothing I would be worried about, especially if you are getting 100+ anyway :)

 

Maybe thats the issue. I'm flying in VR and it goes from a nice stable fluid 45 FPS + to sub 45 fps stutter fest that makes me want to chunder.:puke:

 

No other module does this (I have all of them). And the very same aircraft at the very same spot on the same runway looking in the same direction is totally fine on takeoff. This only happens after touchdown on landing.

[BIGNEWY]

I fly in VR a lot, I do get some reduced frames in airfields, even down to about 38fps normally at Senaki but is usually smooth for me.

 

Generally 45fps+ in the air at altitude 50+ and over the ocean can go to 60 - 90 fps depending on altitude.

[Deano87]

Huh. Well I don’t know what to tell you. It’ drops to about 50% the FPS as it should be (based on the same aircraft, same location, same viewing direction but not after landing) so that seems pretty weird to me.

 

Take a look at page 6 of this thread and look at some of the stuff Tepnox found.