VR Performance investigation.

[some1]

Sure, I added those missions to the first post in that thread.

 

If you manage to get constant 45 fps in the Rift, then with ASW it will be smooth for most of the time. Although the Huey is one of the least demanding aircraft and an empty free flight mission is hardly taxing your PC.

[hansangb]

Thanks, I guess i required Su-27 which I don't have. But will play around. I'm in the process of setting up a laptop to act as a host to improve VR performance. We'll see how that goes.

[some1]

Just switch to a different aircraft. All aircraft were tested in the same situation.

[fitness88]

Hi folks,

I've been bashing my head for the past few months with VR performance issues in DCS on my rig.

 

I've been following whatever tips I could find and Ended up belly up all the time.

I will not put it as "un-playable" but in some scenarios it's definitely not very "stomach friendly" I've not very prone to motion sickness, so I can "deal with it".

 

I'm experiencing framerates as low as 18 in airports (Mirage 2000, instant action, takeoff) going up to 90 above 15k over the sea. going over land will give me 60. low altitude is 30-45.

 

lowing everything to minimum definaly makes frame rate go up, but immersion plummets as I can't read gauges, or feel anything close to real life. (I "need" x1.5 PD, HDR and (at least) "flat" shadows). which is what I get for the framerates above.

 

My spec is as follows:

i7-2600K @ 4.2

24GB RAM (2*4+2*8)

GTX1080 (which goes up to 2Ghz)

 

and I have a secondary GTX750 I use for some extra monitors and NVENC video encoding).

 

I've recorded a 12 minute clip of a quick flight, (M2K, takeoff from IA). with the Steam VR frame timing on top

 

the OSD wasn't recorded, but sitting on the runway (with 18-25 fps) my GPU load was 40%.

also looking at the timing data, it seems that I'm very much CPU bottlenecked.

 

SteanVR timing data from their developer wiki:

https://developer.valvesoftware.com/wiki/SteamVR/Frame_Timing

 

Can someone have a second look before I start saving up and working on approval from upper management? :)

 

I'll be waiting a month or so for the Gen 8 Intels first anyway.

 

and if someone can post another frame timing data from SteamVR or a rift with a better CPU for comparison, it would be greatly appreciated. (attached my current graphics settings - pretty much "VR" preset with high textures. and my PD is set to 1.5)

 

if someone can think of a better or additional tests to preform (call it "DCS VR benchmark guidelines"). feel free to suggest.

 

Cheers,

Uri

 

 

=== Update 1 ===

It seems that MSAA (and AA) are not an issue in this scenario, as both seem to be GPU only workload and in my case, had minor effect.

 

Shadows on the other had, had a major impact. And with shadows off, FPS very rarely dropped below 45fps while not directly in the airport.

 

HT enabled or disabled seem to have little effect. But I'll need to look at that more closely.

 

=== Update 2 ===

I've ran a second round with all shadows off. frame rates were noticeably higher. (same exact settings, just without shadows)

but flying low with no shadows feels weird.. but if that is the price to pay.. :(

 

 

bottle neck is definitely CPU..

now it's time to wait and see what intels comes up with.

 

is there anyone here with a ryzen that can post similar video? just to see how it handles VR?

 

Next Up.. bumping up PD to 2.0 as this is pure GPU load, and mine "just sits there"...

 

 

Try running ASW in 'Auto' if you're not already.

[uri_ba]

In steamVR it's called "asynchronous reprojection", And it's enabled by default :)

it does not "magically" increase frame rates. just make the lower frame-rates tolerable..

 

 

I've already have a bunch of videos with a bunch of different settings..

I still need to draw my conclusions of them. but from what I've seen, it seems that in my rig, the CPU is bounding at PD1.5 but from 2.0 and up it's going into GPU limit territory.

 

with "VR" preset, increased Textures to High, shadows OFF and x8 MSAA (hadn't tried more) and PD1.5 I get exceptable frame rates. (lows at about 30, most of the time on 45 and 60/90 at higher altitudes)

Edited July 3, 2017 by uri_ba