From: Mark Evans (mrrevans++at++yahoo.com)
Date: 03/06/2002 09:44:17
I use Linux RedHat 7.2 and Performer 2.5, on a P4
1.8GHz with GeForce 3 Ti 200. I have an app that
spends most of its time in the draw callback (App and
Cull are taking less than 1 ms per frame, Draw is
around 14.8 ms).
I have __GL_SYNC_TO_VBLANK set to 1, and in uniprocess
I get a constant 60 Hz frame rate (the monitor is set
to 60 Hz).
Even if my computer has only one processor, I wanted
to test the PFMP_APPCULL_DRAW setting, which didn't
offer the expected results. Although the Performer
stats say that the Draw process takes a little less
time (which is also curious, since the whole drawing
should be performed on the video board, not CPU) -
13.4ms instead of 14.8 ms, at times I get a continous
switching between 30Hz and 60 Hz - that is the elapsed
time between one frame and onother is 16.6 ms, then
33.3 ms, then 16.7, then 33.3, and so on. I also get
sometimes a constant 60Hz rate.
Is there a logical answer to this? What is happening?
Could such an app as mine benefit from multiprocessing
(since App and Cull takes so little as compared to
Draw)? In the future I need to run this app on a
multiprocessor Linux.
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This archive was generated by hypermail 2b29 : Wed Mar 06 2002 - 09:44:26 PST