glDispatchCompute calling overhead
I'm facing an annoying problem (or is really?) that every call to glDispatchCompute ALLWAYS comes with an annoying overhead of about 0.2ms.
Just make it clear: Even executing a “glDispatchCompute(0,0,0)” call on an EMPTY shader cost 0.2ms.
- Does this make sense?
- Is it NVIDIA only issue?
- Is there a way around this?
*Note1: The 0.2ms is measured using “glBeginQuery(GL_TIME_ELAPSED,...)“
*Note2: Platform is GTX-560, Windows 7, Latest NVIDIA drivers.
Last edited by edoreshef; 04-23-2014 at 11:56 AM.
I am also having this issue. I get the exact same delay ~0.2ms when measuring with glBeginQuery(GL_TIME_ELAPSED, ...).
For reference, I am on Windows 7 with GTX-470 on the latest drivers.
Could someone shed some light on this?
EDIT: I have just tried the same thing on a GTX-780 and the delay disappeared. I guess the delay was something only present in 560 and below?
Last edited by inutard; 05-12-2014 at 05:35 AM.