I’m running Psychtoolbox on Linux and I got “PTB-WARNING: Failed to start gamemode optimizations:” after ~450trials in my experiment. It is weird because everything looks fine at the start, but the warning just suddenly appear at the middle of the experiment and pop up every trial until the end. After the experiment, if I restart matlab and run the code again, the warning comes up in the first trial. The only way to eliminate it is to restart the computer. But the warning will still come up at ~450 trials in the next experiment.
The duration of each trial varies. But I guess it may be 2-3 seconds on average?
Have you had the same issue? Any suggestion on what to look into?
Some more details on the soft- and hardware.
Psychtoolbox 3.0.17
Linux: Ubuntu 5.4.0-81-lowlatency
3 monitors: Vpixx 3D, Eizo FG2421 and Dell. Vpixx and Eizo are configured as the same X screen with refresh rate 100Hz to display stimuli.
Graphic card: NVIDIA GeForce GTX 980 Ti
Is your Ubuntu up-to-date, and are you using the open-source drivers? I’ve never seen that error on any of my workstations, but they all use AMD GPUs and perhaps this is an NVidia-linked problem? You could try to run SetupPsychToolbox.m in MATLAB after changing the the PTB root folder again to ensure that gamemode.ini file is the latest one installed by PTB… Or you can check/copy it manually (the source is in Psychtoolbox/PsychBasic/gamemode.ini and the destination is in /etc/gamemode.ini I think)…
Gamemode gets enabled if you call Priority(n) with n>0 ie. realtime mode, and disabled for n=0.
The way you should use Priority() is once at the beginning of your script, once at the end. Calling it all the time, e.g., each trial is counterproductive, could actually impair timing instead of helping it, due to the inherent overhead.
Error messages for reasons of gamemode problems would be found in /var/log/syslog, e.g., tail -f /var/log/syslog.
Any further assistance from myself will require buying paid priority support, but not calling Priority all the time would be a good start.
