I’m using glCompressedTexSubImage2D with a PBO. I’ve noticed that most of the time the call takes much less than a millisecond, but other times the call seems to block for more than 30 milliseconds.

Is there anything I can do to fix this problem?


I’m still trying to figure out what’s wrong. I was unable to reproduce the problem in a test program. However, I was able to collect some data that may be helpful. Geforce 7 series cards seem ok, but we’ve seen frame breaks with the 8 series and the GTX 280. We haven’t noticed anything special about the parameters to glCompressedTexSubImage2D, but frame breaks seem to occur consistently after about 44 MBs of texture uploads no matter how fast we move the eyepoint. (We get frame breaks even when we stop moving the eyepoint for a minute.)

If anyone has any ideas, I’ll give them a shot.


Just yesterday someone here mentioned that there were some old drivers from nVidia, that do that problem on every 46MB, and this bug has been fixed in newer drivers.

I just saw that post, thanks for the link. Unfortunately, I tried latest beta driver (177.13) and release driver (173.14.12) for 64 bit Linux.

I still have the problem.