Multicore + V-sync = Jittery movement
dethovu
Join Date: 2009-06-23 Member: 67906Members
Join Date: 2009-06-23 Member: 67906Members
<div class="IPBDescription">ever since build 225</div>A strange bug that I don't see anyone else mentioning, so I thought it was worth creating a topic to point it out. I can't imagine it is just me, as my PC configuration is pretty standard fare.
Here's the problem:
Enabling V-sync (double or triple, doesn't matter) and Multicore <i>both at the same time</i> causes jittery movement. Framerate stays locked at 60 (since v-sync is on), but when I move, it jitters (still showing 60 fps). It reminds me of what happens when a CPU goes to 100% and you get a tick-tick-tick-tick type stutter that is rhythmic.
Disabling either v-sync or multicore (or both) returns the game back to fluid movement.
HOWEVER: While v-sync is ON, disabling Multicore fixes the stuttering, but all 4 of my cores are still used at the same % levels as when multicore is ON.
<b>To summarize:</b> In order to use v-sync, I have to play with multicore OFF to make the game playable, but the engine still uses all the cores as if multicore is ON.
It is certainly worth mentioning that I haven't had a single problem using either multicore or v-sync up until this point all throughout beta. Maybe it is also worth mentioning that if I force v-sync through a third party program, instead of through Spark, it still produces the stuttering (only if Multicore is enabled, though).
i5-3470 // 1GB 6850 // 8GB // Recon3D // Win7 x64
Here's the problem:
Enabling V-sync (double or triple, doesn't matter) and Multicore <i>both at the same time</i> causes jittery movement. Framerate stays locked at 60 (since v-sync is on), but when I move, it jitters (still showing 60 fps). It reminds me of what happens when a CPU goes to 100% and you get a tick-tick-tick-tick type stutter that is rhythmic.
Disabling either v-sync or multicore (or both) returns the game back to fluid movement.
HOWEVER: While v-sync is ON, disabling Multicore fixes the stuttering, but all 4 of my cores are still used at the same % levels as when multicore is ON.
<b>To summarize:</b> In order to use v-sync, I have to play with multicore OFF to make the game playable, but the engine still uses all the cores as if multicore is ON.
It is certainly worth mentioning that I haven't had a single problem using either multicore or v-sync up until this point all throughout beta. Maybe it is also worth mentioning that if I force v-sync through a third party program, instead of through Spark, it still produces the stuttering (only if Multicore is enabled, though).
i5-3470 // 1GB 6850 // 8GB // Recon3D // Win7 x64
Comments
The limited framerate does not behave how it typically would if it was the same FPS without the limiter.
I'll try and keep you posted in this thread.
use profile in the console and walk around a bit.
See if you can capture the areas which seems jittery but pressing the space bar to pause the profiler. then expand the tree by clicking the plus symbols.
Post some screens in here after.
Great, thank you! That was the main purpose -- to let them know.
It plays just fine if I leave Multicore off, so no biggie for me personally -- but definitely a problem that needs addressing. I'm sure they'll have it figured out before too long.
EDIT:
After reading your post again I realize I think we're talking about two different things. My issue isn't so much v-sync related as it is Multicore related. I answered your post in the other thread you refereed to <a href="http://www.unknownworlds.com/ns2/forums/index.php?s=&showtopic=122427&view=findpost&p=2001821" target="_blank">here</a> a few days ago.
V-sync works just fine as long as multicore is disabled. It is only when both MC and V-S are enabled that it becomes an issue.
The jittery you're referring to reminds me of typical v-sync jitter when the frame buffer can't keep up with the refresh rate, in which case switching between double and triple buffering tends to fix that type of issue. But that's not the type of jitter I'm getting -- it's more of a 100% CPU usage type jitter that has a rhythmic tick-tick-tick-tick pattern, except the CPU isn't at 100%
Everywhere -- doesn't matter where. Even in areas where I get 120+ fps with v-sync off, or a rock solid 60 with v-sync on, it jitters. It's very rhythmic, too -- it doesn't seem to matter what or how much is being processed.
Tried changing all of my settings/lowering them and nothing worked. Ran across this and disabled multicore rendering while having vsync enabled and it goes away, regardless of what graphics settings I have enabled (maxed in my case) Regardless of disabling it, my cpu is still using all 4 cores, not entirely sure how multicore rendering operates though.
i5 2500k
HD 6950 2gb
8gb 1600 ram
*Edit* I tried to capture it on Fraps using both 30 fps and 60 fps capture although with this recording the jitter goes away completely, regardless of having vsync and multicore rendering enabled. I think it just has to be related to being at or very near 60 fps with both enabled, as by recording you lock your fps to 30 or in my case locking Fraps at 60 actually drops my fps down to between 30-40 fps.
Happy to finally see someone having the same issue -- although I'm sorry you're having an issue at all! But this certainly makes me feel a bit better knowing it isn't just me.
I wonder if locking the fps to something lower than 60 like 59 would fix this? Gonna look for a way to do this, will report back.
Just as Avengersoul surmised, limiting your FPS completely fixes this issue.
I have found relief by limiting my framerate to "59" with a program called MSI On-Screen Display Server that is bundled with MSI Afterburner found <a href="http://event.msi.com/vga/afterburner/download.htm" target="_blank">HERE</a>
I will post a new thread with this information as I believe it is a very big deal until there is some sort of fix or some type of frame limiting variable is included in-game.