CPU Bound (rendering thread)

[KEULE]

Hello everyone,

my testbed is the instant action Free Flight mission for the F-16 on Syria. Usually I am getting here around 45-55 FPS. With the latest patch on Multithread I only reach up to max 30 with the message: CPU BOUND (rendering thread). See attached screenshot.

Does anyone know what this mean? Is the CPU somehow capped? What can I do to get better results?

 

Thank you so much for all your help!

 

My specs: Intel i7-8700K @ 3.70GHz, 32 GB RAM, GeForce RTX 3070 Ti, VR Headset: Pimax 5K Plus, Windows 11 is up-to-date and runs on an SSD, DCS on an NVMe.

[Andy4578]

I get exactly the same as this when using the MT version.  I don't get this in the ST version.

My specs - AMD 5800xt3d, MSi X-Trio 6800xt, 32GB RAM, 1TB pcie4 M2, Reverb G2, Win 11.

[TZeer]

Have the same thing. CPU bound.

 

5800X, 6900XT, 32gb RAM, win 10, Reverb G2.

[Gryzor]

Me too. 4090, 5900x, 32gb RAM, Win 10, Valve Index

[BluePhoenix]

same here

seems to be working great in 2D but VR is locked to 1 P-core and all E-cores

 

[Hotdognz]

I get the same msg using MT, 4090, 13700K, 64gb DDR4, Win10, G2

[Hendry30]

Same thing.....in MT

Win 10 ,64gb ram,zu590,I711700F,rtx3080TI,g2 reverb,openxr.

Edited March 11, 2023 by Hendry30

[Wali763]

Me too. CPU bound (rendering thread). In light missions CPU-frametime (according to frame-timing-overlay in OpenXRTools for WMR) in MT is higher than without MT. Seems wrong to me.

5800X3D, RX6950XT, 32GB, G2, Win10

[Major_Mayhem]

Same

I have a R9 5900x CPU, RTX3080 (10g) GPU, 64gb DDR4 Mem, Valve Index VR.

However from what I've been told this is the same for everyone unless their running a low performance or older GPU and that the CPU bound means all your cores are being used and that Red means that one or more cores is maxed out.

I have separate issues with MT that I will make a bug report on.

Edited March 11, 2023 by Major_Mayhem

[Dec_Cetera]

Same/similar issue.

CPU bound, locked to 31fps (even in menu) switches between "Main Thread" and "rendering thread" this happens on all "free flight" missions in the caucases (F16 and F18) and I'm looking at about 2 frames on Syria in the AH64 hot start mission.

Bizarre because task manager shows my GPU usage and 90% or more (but I assume it scales based on the load)

TM also shows 1 core being used far more than the others, not seeing TM show much of a difference in terms of core distribution between MT and before.

I haven't added the command line to the .exe (because I honestly don't know how) but DCS launches and goes straight into VR mode with my headset connected. I'm definitely using the new .exe in the bin-mt folder though. 

Specs: Ryzen 5 2600x, 32gb ram, Nvidia 2070, DCS installed on NVME drive, Oculus Quest 2 running Open XR (Steam VR disabled)

Edited March 12, 2023 by Dec_Cetera
Add more info

[Tophatter14]

Same, with Quest 2. 

12th gen i9-12900K processor with a 3080TI GPU

[prestonflying]

i7-12700KF, 3080, 32GB Ram, HP G2, NVME.

2D 3440x1440 getting 170+Frames with "GPU BOUND"
VR HP G2 render getting 50ish frames with "CPU BOUND (rendering thread)"

Interesting OP is pegged at 30FPS, perhaps you have Nvidia Frame limiter enabled or Motion Reproduction/AWS which might be locking your frames at half your headset HZ. Or maybe something with vsync is enabled?

Edited March 12, 2023 by prestonflying

[havok2]

6 minutes ago, prestonflying said:

i7-12700KF, 3080, 32GB Ram, HP G2, NVME.

2D 3440x1440 getting 170+Frames with "GPU BOUND"
VR HP G2 render getting 50ish frames with "CPU BOUND (rendering thread)"

Interesting OP is pegged at 30FPS, perhaps you have Nvidia Frame limiter enabled or Motion Reproduction/AWS which might be locking your frames at half your headset HZ. Or maybe something with vsync is enabled?

 

Hey, I have a 5800x3D, 32GB DDR4-3200-CL14, RTX 4090, Pimax 8KX and normally I get stable 75fps with my settings. But now after I ran MT and it starts for some seconds in Steam Cinema mode I only have <30fps even in the main menu. I can hear my GPU coilwine because of the stuttery cpu. You can see it in fps VR (screenshot). Something is not correct here. Unplayable for now.

[NineLine]

5 hours ago, KEULE said:

Hello everyone,

my testbed is the instant action Free Flight mission for the F-16 on Syria. Usually I am getting here around 45-55 FPS. With the latest patch on Multithread I only reach up to max 30 with the message: CPU BOUND (rendering thread). See attached screenshot.

Does anyone know what this mean? Is the CPU somehow capped? What can I do to get better results?

 

Thank you so much for all your help!

 

My specs: Intel i7-8700K @ 3.70GHz, 32 GB RAM, GeForce RTX 3070 Ti, VR Headset: Pimax 5K Plus, Windows 11 is up-to-date and runs on an SSD, DCS on an NVMe.

If you are seeing your frames limited make sure there isnt some vsync or other setting somewhere outside DCS affecting this. Even check and see if you have an autoexec file in your Config folder in saved games to make sure its not limited there.

[havok2]

5 minutes ago, NineLine said:

If you are seeing your frames limited make sure there isnt some vsync or other setting somewhere outside DCS affecting this. Even check and see if you have an autoexec file in your Config folder in saved games to make sure its not limited there.

V-Sync and Framelimiter disabled in NVIDIA Controle Panel and DCS Settings. No Autoexec file in my settings. Maybe it has something to do with this cinema mode from steam? When I launch MT Mode I get a popup that DCS has a native VR mode. I only can cancle or accept here. When I accept it starts in VR in cinema mode. Its kind of 2D in VR mode. After some seconds this mode closes and the normal VR mode starts with MT support. But with the first frame its jittery. Its a clean install. Using also latest drivers. No mods.

I tried to run it directly from bin-mt folder with flag  --force_enable_VR - but after some seconds the app shows up in task manager but closes.

Edited March 12, 2023 by havok2

[NineLine]

4 minutes ago, havok2 said:

V-Sync and Framelimiter disabled in NVIDIA Controle Panel and DCS Settings. No Autoexec file in my settings. Maybe it has something to do with this cinema mode from steam? When I launch MT Mode I get a popup that DCS has a native VR mode. I only can cancle or accept here. When I accept it starts in VR in cinema mode. Its kind of 2D in VR mode. After some seconds this mode closes and the normal VR mode starts with MT support. But with the first frame its jittery. Its a clean install. Using also latest drivers. No mods.

I tried to run it directly from bin-mt folder with flag  --force_enable_VR - but after some seconds the app shows up in task manager but closes.

 

Have you tried OpenXR? --force_enable_VR --force_OpenXR

[KEULE]

10 hours ago, NineLine said:

If you are seeing your frames limited make sure there isnt some vsync or other setting somewhere outside DCS affecting this. Even check and see if you have an autoexec file in your Config folder in saved games to make sure its not limited there.

Thanks for your swift reply. I doubled checked and can confirm that no V-Sync is enabled. Unfortunately I dont know how to check for any autoexec file in the saved games config folder. Eveything vanilla in there. Can you or someone else elaborate how to check please? Should there be a specific file or entry within a file?

In the menu my FPS are capped at 45 whereas in the mission its 30 FPS. 

 

Edited March 12, 2023 by KEULE

[KEULE]

UPDATE

After having literally everything else turned on/off by way of try and error I was able to increase FPS even though the "CPU BOUND" message is still present.

So, I was able to increase the FPS from 30 to around 45-50 (it jumps in between and is no longer fixed) by turning off "Compatible with parallel projections", "Smart Smoothing" and "Hidden Area Mask" withing the PiTool settings' Games tab. As you can see from the screenshot the CPU is now at 53% (before around 44%).

However, would be great if someone is able explain what "CPU BOUND" really means and, no less important, finds a way to have it unbound. Any IT experts around?

 

Edited March 12, 2023 by KEULE

[Koekemoeroetoe]

Here I'm also CPU bound (main thread and rendering thread), against expectations. Either my understanding of the term "CPU bound" is incorrect, or something weird is going on.

Specs: i9 10850k, 64Gb DDR4 3600MT/s, RTX 2070, HP Reverb G2 and using OpenXR, 90% resolution and MR turned off.

I do see a slight improvement over the ST version of DCS though, talking about an increase of 2-5 FPS. Nevertheless the ingame FPS counter states I'm CPU bound, while my GPU is hitting 99-100% usage consistently, which I would say means I'm GPU bound. I've done most of the tweaks and checks suggested here, but I remain CPU bound. Turning up or down all visual settings makes no difference.

[breetai]

16 hours ago, BluePhoenix said:

same here

seems to be working great in 2D but VR is locked to 1 P-core and all E-cores

 

I have the same issue, only 1 P core and all E cores working in VR.

[diego999]

Same here. First CPU core maxed out even in the main menu and "CPU bound main thread" message in red letters. Something is clearly wrong.

i5 10400F, 32gb RAM, 3060ti, Quest 2.

Weirdly, this only happens in VR with the mt version. 2D no issues, non-mt VR, no issues.

[sammich318]

Same thing.  CPU bound (main thread). 7900x3d and 3090.  I e been trying to solve for three days.  Probably won’t get a solution for a while

[twanmal]

with the G2 and openxr,  it does not occure anymore by switching "motion Reprojection" to "Disabled" in OpenXR Runtime. This is surely not what we want, but I hope it may help some of us.

Edited March 12, 2023 by twanmal
grammatical

[bart]

Same here.

I have an i7-12700K and Asus ROG 3090.

Shows CPU bound on the DCS FPS window. I guess it's caused by one core at 100%.

[tangobravo]

Same here, 12900k, 3090ti,  CPU bound main thread and rendering thread.