AnsweredAssumed Answered

GL 4.4.12874 Texture array clear performance

Question asked by Taz1024 on Apr 25, 2014

Hi,

 

I ran into an unexpected performance issue with clearing 2d texture arrays, so I tried some work-arounds. The huge differences in gpu time seem to indicate there's something wrong with the implementation of clears (clearbuffer, cleartexsubimage) for 2d arrays. Here are the results:

 

rgba16f, 64x64x192:

- glClearBufferfv(): 400us

- glClearTexSubImage: 400us

- Draw 192 slices: 136us

- Compute: 35us

 

depth24s8, 64x64x192:

- glClearBufferfi(): 334us

- glClearSubTexImage(): 334us

- Draw 192 slices: 27us

- Compute: no image store avail for depth-stencil =(

 

Also worth noting is that clearbuffer and clearsubteximage take about ~40us cpu setup time compared to compute setup of ~15us.

 

cheers,

-mh

Outcomes