Multithreading Performance is Sensational in VR

[Flextremes]

Rocking a 4090/5800x3D here...

F18 ready for launch on Carrier: now openXR shows 3.3ms app CPU and 3.2ms rdr CPU times...

Single-threaded openXR shows 5.1ms app CPU and 4.2ms rdr CPU times...

Seems like there have been more optimizations having a positive impact (ie Shadows flat bug).

Edit:

Good news maybe if MT does not work for you, it looks like single-threaded DCS is also much smoother.

After more testing, I can also safely conclude that single-threaded is also much more smoother and responsive. I prefer to fly with Flat-shadows, which clearly is smoother. I improved by 1-2 ms GPU frame times in the F16 in the above Dubai and Marianas in single-threaded.

MT is even better, improved by 2-3 ms GPU frame times in the F16 in the above Dubai and Marianas.

Obviously MT is much smoother, there are less stutters, but maybe more noticeable: input latency improved considerably (might be placebo). DCS feels much more snappy and responsive.

Edit 2:

I am genuinely impressed. Both Syria and Marianas maps are clearly much more smoother/responsive. The positive impact on CPU also affect GPU response times favorably. Did not expect this, because with a 4090 less GPU bottlenecks are experienced. 

Edit 3:

DCS MT seems stable so far, no CTDs yet, but only limited/quick tests of many different missions and instant actions. When starting a mission, you can see all textures (plane and ground) being loaded in. After a few secs, all is fine. 

So far I have never seen CPU time more than 10ms. 

Edit 4:

I just went from low shadows to ultra, enabled cockpit global illumination, from 60% trees to 100% and all is still perfectly smooth (higher FPS than before MT update). 

Edit 5:

Compare below the OpenXR CPU and GPU frame times in Single threaded and Multithreaded: F-18 on carrier ramp in Persian Gulf: 

1st: Single Threaded...

Secondly: Multi-Threaded

Edited March 11, 2023 by Flextremes

[rudek]

hp g2  5900x 6900xt  64ram(3200) same fps  no boost + light problem

fps test.trk

Edited March 10, 2023 by rudek

[DirtyMike0330]

Here we go with the immediate "this is amazing" posts lacking any supporting data. "now openXR shows 3.3ms app CPU and 3.2ms rdr CPU times..." is a completely unhelpful statement. 

[despinoza]

like always depend entirely in what was your bottleneck. OP owns a 4090.

I have the same system 4090 5800x3d and i see the upgrade in heavy scripted situations.

Edited March 10, 2023 by despinoza

[Flextremes]

6 minutes ago, DirtyMike0330 said:

Here we go with the immediate "this is amazing" posts lacking any supporting data. "now openXR shows 3.3ms app CPU and 3.2ms rdr CPU times..." is a completely unhelpful statement. 

I added results single threaded for comparison, what do you mean?

[DirtyMike0330]

3 minutes ago, Flextremes said:

I added results single threaded for comparison, what do you mean?

Oh you mean the edits you made after I already responded to your original post? ::eye roll::

[Flextremes]

2 hours ago, DirtyMike0330 said:

Oh you mean the edits you made after I already responded to your original post? ::eye roll::

Seriously, that edit was done way before I read your complaint, you are simply too fast to pull the trigger. Don't mind me making more edits with new conclusions, because this patch is pretty amazing. I hope you enjoy the MT update like I do. Why don't you share some of your own findings...

Edited March 10, 2023 by Flextremes

[DirtyMike0330]

16 minutes ago, Flextremes said:

Seriously, that edit was done way before I read your complaint, you are simple too fast to pull the trigger. Don't mind me making more edits with new conclusions, because this patch is pretty amazing. I hope you enjoy the MT update like I do. Why don't you share some of your own findings...

I intend to, thanks 

[Dragon1-1]

1080ti with 5800X3D, initial test, headset gets pegged at 40FPS in situations where it used to run on 20-30 before (F-16 training missions, not anything super complex). That's without any further steps taken, just ran the MT branch right after it downloaded. No doubt it can be optimized further.

I still want to move up to a 3090 (mostly to take advantage of DLSS when it comes), but this looks amazing already. For the first public iteration, it's great. Looking forward to further improvements, Vulkan in particular (although by the time that one comes out, I'll probably have the 3090).

[Panthera_Tigris]

No change for me because I was probably already GPU bound

My CPU frame time was already 3-4 ms which is very good so I don't think it could have improved much.

Meanwhile, my GPU frame time ranges from 12-15 ms. Guess I should reduce some settings because 15 ms is way too high with a 4090.

• CPU: 7950X3D
• GPU: 4090 FE
• Reverb G2 with 150% OpenXR resolution and max settings (except 2x MSAA)

Also, the MT DCS is running on my non v-cache core for some reason even though I have it set to prefer v-cache in Process lasso. Not that it matters because even if I force it to run on v-cache, there is no perceptible change. 

[Flextremes]

18 minutes ago, Panthera_Tigris said:

No change for me because I was probably already GPU bound

My CPU frame time was already 3-4 ms which is very good so I don't think it could have improved much.

Meanwhile, my GPU frame time ranges from 12-15 ms. Guess I should reduce some settings because 15 ms is way too high with a 4090.

• CPU: 7950X3D
• GPU: 4090 FE
• Reverb G2 with 150% OpenXR resolution and max settings (except 2x MSAA)

Also, the MT DCS is running on my non v-cache core for some reason even though I have it set to prefer v-cache in Process lasso. Not that it matters because even if I force it to run on v-cache, there is no perceptible change. 

Interesting: I consistently get lower CPU and GPU times in all maps and airframes: (app CPU in the F15 in Nevada is below 1 ms ). AH64 on the Marianas map in a mission I get easily 45fps.  I can imagine that other optimizations (like the flat-shadow fix)  are even more responsible for this.

I also use process lasso, assigned exclusively DCS to core 0-7 without HT. On the last core I run all other windows and app processes. Maybe you can try with disabling the second core in bios, some game perform even better (than with core parking enabled on the second). 

Edited March 10, 2023 by Flextremes

[smickums]

no noticeable improvement. VR: Reverb G2, i5 12600k, rtx 4080, 64 gb ddr5 xmp enabled 5600

example.trk

[Flextremes]

20 minutes ago, smickums said:

no noticeable improvement. VR: Reverb G2, i5 12600k, rtx 4080, 64 gb ddr5 xmp enabled 5600

example.trk 9.48 MB · 1 download

I am getting app CPU 2ms, rdr CPU 3.4ms and app GPU 12-13ms when you fly back over the airfield in your trackfile. Both CPU and GPU frame times are consistently low for me.

Edit: over the city at the sea app CPU 2ms, rdr CPU 3 and app GPU 10-15 ms.

Edited March 10, 2023 by Flextremes

[smickums]

is DLSS available yet? not seeing it anywhere

[Supmua]

I haven’t done any testing but personally find it hard to believe that CPU frametime would be in 2-3ms range with this update.

[crispy12]

Unfortunately it's constantly crashing for me using virtual desktop and the Pico 4.

 

Tried clean repair but still no luck

[Flextremes]

8 minutes ago, crispy12 said:

Unfortunately it's constantly crashing for me using virtual desktop and the Pico 4.

 

Tried clean repair but still no luck

That sucks! Mayby delete your shader caches? Also try single thread DCS, for me it is also smoother. Good luck!

[fargo007]

I am seeing an improvement in multiplayer. 

As compared on a specific server I was previously seeing 40-45fps, now over 60.  

Ryzen 6, 2080ti. Essentially default VR settings with a few tweaks.

[YoYo]

How to start DCS MT with Staem VR, so default system for VR for DCS now????

[smickums]

so i just found out that you may need to be running windows 11 to see full performance boost. i'm updating to it now to see what it's like.

[Nodak]

Installed a new 4090 wednesday, so was testing settings the past two days trying to optimize best ones for me with the same mission, AH-64 runway take off Guam, always the same route straight to the two destroyers in the harbor, max fps I could squeak out landing and parked on the destroyers pad was 61, post patch 91, so a definite jump for me.  11900K with 32 ram.  First time ever flying across the entire Island out to the carrier group that was good.  Only used the map for max stress testing, was basically unplayable, not any longer.

Think I can crank up a bit more on eye candy even.  It is slower loading in the map, and I had all water and no terrain while waiting in pause for a while.  Never happened before, but once loaded she was good to go, buttery smooth flight.

[Flextremes]

30 minutes ago, smickums said:

so i just found out that you may need to be running windows 11 to see full performance boost. i'm updating to it now to see what it's like.

I'm on 10: highly optimized. I clearly do notice a significant boost. How do you come to this conclusion?

Edited March 10, 2023 by Flextremes

[X_legio]

Hi, we have to continue to use the --force_enable_VR --force_OpenXR parameter to have the native openxr ?

Edited March 10, 2023 by X_legio

[Flextremes]

37 minutes ago, Nodak said:

Installed a new 4090 wednesday, so was testing settings the past two days trying to optimize best ones for me with the same mission, AH-64 runway take off Guam, always the same route straight to the two destroyers in the harbor, max fps I could squeak out landing and parked on the destroyers pad was 61, post patch 91, so a definite jump for me.  11900K with 32 ram.  First time ever flying across the entire Island out to the carrier group that was good.  Only used the map for max stress testing, was basically unplayable, not any longer.

Think I can crank up a bit more on eye candy even.  It is slower loading in the map, and I had all water and no terrain while waiting in pause for a while.  Never happened before, but once loaded she was good to go, buttery smooth flight.

I literally went from flat shadows to ultra, enabled cockpit global illumination, from 60% trees to 100% and all is still perfectly smooth (higher FPS than before MT update). 

Can anyone suggest a track or mission file that is known to really punish CPU in DCS?

Edited March 10, 2023 by Flextremes

[Zebra1-1]

1 hour ago, smickums said:

is DLSS available yet? not seeing it anywhere

DLSS and Vulkan will be later.