Bug #14189

Extremely unstable FPS rate

Added by roboblocky 18 days ago. Updated 8 days ago.

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My PC:
Intel (iGPU 530)
Linux Mint 18.1
Oibaf/Padoka Mesa PPA

For about two weeks now, KSP is suffering from a very weird performance issue.
The framerate seems fine overall (50-60fps), but the frames are seemingly delivered extremely uneven, so that the game actually stutters heavily. The stuttering is absolutely unrelated to graphics settings, I tried both the usual (1080p with high details) and lowest possible settings (720p with every detail reduced to lowest) with the same result.
Furthermore, not only the game itself is stuttering, but the desktop itself is stuttering with exactly the same rhythm.
The only change in my system I could maybe relate to the issue is an update to the mesa library through the oibaf-ppa. Other OpenGL based applications run fine. (I tested XCOM)
Unfortunately, reverting to an earlier version of mesa and the many related libraries goes beyond my knowledge right now.

ksp_perf_1.png View (314 KB) roboblocky, 03/12/2017 12:36 PM

ksp_perf_2.png View (409 KB) roboblocky, 03/12/2017 12:36 PM



#1 Updated by gfrodo 18 days ago

I can confirm this bug.

My configuration:
Linux Mint 18.1
Intel 6200U with 520 Graphics
Standard Mesa driver (no ppa)
KSP 1.2.2
V-Sync: every V-Blank
Frame Limit: 60FPS

Framerates (min;avg;max):
Start screen: 25;45;170
KSC: 25;35;140
Craft in orbit: 25;29;45
Landed craft: 25;44;90

In flight, the average framerate is low, because of my graphic settings and the power of my Intel GPU, but steady. With higher average framerates like at the KSC, Tracking Station, the frames are more bumpy. Sometimes in flight (maybe once every few hours) the screen hangs for up to 0.5s without any reason.

Another GPU application like glxgears gets very stuttering when KSP is running too, but has constant average 60FPS (with v-sync), no matter whether KSP is running or not.

#2 Updated by AlffromKerbal 16 days ago

Tried deactivating v-sync?

Once i had massive playability problems at a game, after i turned off v-sync, it ran like a charm.

#3 Updated by roboblocky 16 days ago

Yes, no change.

#4 Updated by sal_vager 8 days ago

  • Priority changed from High to Normal

#5 Updated by sal_vager 8 days ago

  • Status changed from New to Need More Info

Hi, KSP 1.2.2 has not had any changes in the last 3 weeks, so if it was running fine before this is should be running fine now unless there is an external issue.

Please see the wiki and provide your game logs, full hardware/driver information, settings.cfg and the saves you are using.

Please also test with no other programs running, even your browser can be using a lot of memory and cpu which will leave less for KSP.

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