Now getting >90 FPS at 1080p - info on issue affecting high-end rigs [spoilers]

[Astyrrean]

CBJ, Bernd et al,

I have additional data and now a core hypothesis around poor performance on high-end rigs.

Despite getting 15-20fps in the early game, I have continued the plot and to my astounding surprise, in the new sectors (DeVries - after the gate), performance is incredibly better. As in, I get >90 FPS at the lowest graphic setting at 1920x1080, versus the 15-20fps in Albion with the same configuration:

[ external image ]

Jumping back to the Albion system returns the game to the ~20fps:

[ external image ]

Now notably this is not a CPU utilization bottleneck, and neither a GPU fill-rate bottleneck, as you can see from the data. RAM is also fine.

My hypothesis is that it is a thread synchronization issue between the (very numerous) ai-controlled ships in Albion and the other threads. That would explain low utilization and low FPS seen...

Would it be possible to test that hypothesis by a console-command or other toggle in a future version? Or alternate approaches to thread synchronization? I know by hard experience that thread synchronization can be a real bottleneck at high throughput levels - that is the main challenge of parallelism in application development.

90 FPS without SLI is ~150 FPS with SLI enabled, which is more or less in line with what I'd expect to see on my rig at 1080p (remember - I have a 3840x2160 screen and that's 4x the pixels of 1080p).

Best,

Astyrrean

[Cubemonkey]

Well that is an interesting development. Hopefully they see this post.

[TheRealBix]

Do you have GTX 680's ?

If so, i can try to put a supersampling x4 and compare our framerates.

[Freeman_79]

Also take in consideration that Albion is "a lot more" crowded than DeVires.
Alot more ships on the move there.

[Nightdragon81]

Also take in consideration that Albion is "a lot more" crowded than DeVires.
Alot more ships on the move there.

didn't read the post very much did you?

"My hypothesis is that it is a thread synchronization issue between the (very numerous) ai-controlled ships in Albion and the other threads. That would explain low utilization and low FPS seen...

Would it be possible to test that hypothesis by a console-command or other toggle in a future version? "

[Astyrrean]

Do you have GTX 680's ?

If so, i can try to put a supersampling x4 and compare our framerates.

I have a GTX 690, of which half isn't used though, so it acts more or less like a downclocked 680.

[Shenzo]

CBJ, Bernd et al,

I have additional data and now a core hypothesis around poor performance on high-end rigs.

Despite getting 15-20fps in the early game, I have continued the plot and to my astounding surprise, in the new sectors (DeVries - after the gate), performance is incredibly better. As in, I get >90 FPS at the lowest graphic setting at 1920x1080, versus the 15-20fps in Albion with the same configuration:

[ external image ]

Jumping back to the Albion system returns the game to the ~20fps:

[ external image ]

Now notably this is not a CPU utilization bottleneck, and neither a GPU fill-rate bottleneck, as you can see from the data. RAM is also fine.

My hypothesis is that it is a thread synchronization issue between the (very numerous) ai-controlled ships in Albion and the other threads. That would explain low utilization and low FPS seen...

Would it be possible to test that hypothesis by a console-command or other toggle in a future version?

90 FPS without SLI is ~150 FPS with SLI enabled, which is more or less in line with what I'd expect to see on my rig at 1080p (remember - I have a 3840x2160 screen and that's 4x the pixels of 1080p).

Best,

Astyrrean

Nice find~ However from what I read on steam forums Bernd stated that they could give a rats ass abut high end PC's. It sounded like they were setting this game up for future X-Box release and intended it to work low end systems like consoles.

Hopefully they listed to posts like yours and at least have pity on us with decent systems.

[Astyrrean]

I took a screenshot of the worst-case scenario with the most ships on screen.

Down to 15fps... same setup of the 90fps posted earlier... same no CPU nor GPU bottleneck (check stats in top left corner)

http://s21.postimg.org/7395wwa4m/screen ... _01_29.jpg

Compare to the best-case scenario of a highway in DeVries at ~105fps (same settings, same session actually):

http://s13.postimg.org/ukzmj0io6/screen ... _49_20.jpg

Note the important issue here is not how crowded Albion is vs DeVries. It is that in DeVries GPU utilization is actually HIGHER (!). This fact supports the theory above, but of course needs further proof.


{Images posted directly to the forums should not be greater than 640x480 or 100kb, oversize image now linked - Terre}

[Jack08]

Note the important issue here is not how crowded Albion is vs DeVries. It is that in DeVries GPU utilization is actually HIGHER (!). This fact supports the theory above, but of course needs further proof.

It could also be because of a gpu comunication bottleneck, is there any way to see PCI bus usage?

If it is a threadsync issue one would expect the game to run badly even in DeVries, as the rest of the universe doesn't just stop when you leave the area.

There are ways to monitor thread idle/mutex lock time, ill load up visual studio and see if i can get some metrics. it *should* work without code, i think...

[Astyrrean]

Yes, PCIe bus usage is easily monitored. I'll post a screenshot later which includes that. But at 16x PCI 2.0, that can hardly be a bottleneck. Or rather, I'd be really really surprised.

[diistor]

Very interesting! I'd like to confirm that on my setup, how many hours in the game are you to reach DeVries?

[Astyrrean]

It's shortly after the (easily bugged) 100-energy-cell trade mission. Not deep into the game.

[Alexium]

Does your FPS in Albion depend on what you're looking at, what scene is on your monitor at the moment? I, too, have low FPS issues on a decent middle-end rig (i5-2500, AMD 6950), but my FPS heavily depends on whether I look at a station / highway or at the clear skies (although even the best FPS is lower than what I would expect from the lowest possible settings).

[Astyrrean]

Does your FPS in Albion depend on what you're looking at, what scene is on your monitor at the moment? I, too, have low FPS issues on a decent middle-end rig (i5-2500, AMD 6950), but my FPS heavily depends on whether I look at a station / highway or at the clear skies (although even the best FPS is lower than what I would expect from the lowest possible settings).

Yes, clearly depends on what you're looking at. The surprising thing is the GPU utilization going down though instead of up as you'd expect.

[Astyrrean]

Note the important issue here is not how crowded Albion is vs DeVries. It is that in DeVries GPU utilization is actually HIGHER (!). This fact supports the theory above, but of course needs further proof.

It could also be because of a gpu comunication bottleneck, is there any way to see PCI bus usage?

If it is a threadsync issue one would expect the game to run badly even in DeVries, as the rest of the universe doesn't just stop when you leave the area.

There are ways to monitor thread idle/mutex lock time, ill load up visual studio and see if i can get some metrics. it *should* work without code, i think...

Meh having issues with screenshots now. Take my word for it that at 8 Gbps PCIe link speed (i.e. x16 lanes), usage of the video bus hovers between 5-10% as I'd expect.

Or, even better, don't take my word for it and test it on your own system .

[Alexium]

GPU utilization goes down when FPS drops? Did I get that right?

[Astyrrean]

If it is a threadsync issue one would expect the game to run badly even in DeVries, as the rest of the universe doesn't just stop when you leave the area.

Not really, no. If pathing/AI of in-sector ships is handled by a separate thread than the main render thread, you could definitely see that.

Keep in mind that if X3 is any lesson, in-sector and OOS are handled very differently.

Agreed that any background work pertaining to OOS would be the same in both cases, but my argument is about in-sector threading, not OOS threading.

[Astyrrean]

GPU utilization goes down when FPS drops? Did I get that right?

Not normally, no. GPU utilization should be at 100% once FPS starts to drop as the GPU can't keep up.

A GPU utilization below 100% is indication that something else is not "feeding" the GPU fast enough... i.e. bottleneck elsewhere.

Low CPU utilization eliminates that as a bottleneck. Low memory/video bus eliminates that too...

... which leaves threadsync as a hypothesis to test. Unlike X3, XR is multithreaded and the first Egosoft experience at threaded coding that I know about (I may be wrong here though).

[singular1ty94]

I've been screwing around all day with X:R, trying to get my FPS up from about 8 to somewhere in the early teens (with success). Best I've gotten is ~35 in open space, ~20-25 in mid-space and ~8-13 in close space.

I've turned Shadow off, Shaders to low, no AA, no SSAO, V-Sync on, and running in 1366x768 fullscreen. I've mucked around in my nVidia control panel - turning CUDA off gets a big boost, and the biggest boost was making sure nVidia was always running in high performance. Setting xrebirth.exe to run in High Priority helps a bit.

But ultimately the game doesn't run as smoothly as X:TC or even X:AP. My PC is OK, not a massive gaming rig, but I'd expect a bit better frame rate. I can play Skyrim on Very High, to give an example of my laptop's specs.

[Alexium]

Not normally, no. GPU utilization should be at 100% once FPS starts to drop as the GPU can't keep up.

A GPU utilization below 100% is indication that something el.

That much is obvious. What I was asking is does your GPU utilization go down when your FPS drops. If it does - it makes perfect sense.
What I don't understand, though, is why FPS depends so heavily on what direction to face. In light of CPU bottleneck theory, I'd assume that CPU load shouldn't change very much depending on what you're currently looking at. Even if you don't see a highway behind you, that highway still should be processed so that it's in the right state if/when you turn around. I don't know if it's CPU bottleneck, or if the GPU is starving for some specific resource it doesn't have too many of, but it must be something rendering-related.