I'm running the latest linux drivers (319.49) on a 680. I have a big performance problem with glCompressedTextureSubImage3D or glCompressedTexSubImage3D. I am trying to subload into a fairly large array texture 512x512x1000.

The following call goes out to lunch for about 15 ms. Subsequent calls to larger mip levels block for even longer.

glCompressedTextureSubImage3DEXT( bind_name, GL_TEXTURE_2D_ARRAY, 9, 0, 0,
999, 1, 1, 1, GL_COMPRESSED_RGB_S3TC_DXT1_EXT, 8, 0);

The problem was also seen on 580s. I think the 260 driver was ok. I am still trying to reproduce in a stand-alone app, but so far I haven't had any luck. Is this a known bug?