On Tue, Mar 29, 2011 at 03:45:34PM -0400, Jerome Glisse wrote: > Short lived & small bo would definitly doesn't work well for this kind > of API, it would all be a function of the ioctl cost. But i am not > sure the drawback would be that big, intel tested with pread/pwrite > and gived up don't remember why. For the vbo case you describe the > scheme i was thinking would be : allocate bo and on buffer data call > upload to the allocated bo using the bind user page feature that would > mean zero extra copy operation. For the fire forget case of vbo, > likely somekind of transient buffer would be more appropriate.
Just to clarify: Uploads to linear buffers are all done with pwrite (due to an api foobar, it's not so great for 2d/tiled stuff). It's amazing how much faster that is: Switching vbo's from mmpa to pwrite has given a few percent more fps in openarena in i915g! As long as the chunk you're gonna write fits into L1 cache, it's probably a net win. -Daniel -- Daniel Vetter Mail: dan...@ffwll.ch Mobile: +41 (0)79 365 57 48 _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/dri-devel
