On Thu, Oct 23, 2014 at 12:56:46PM +0100, Chris Wilson wrote: > On Thu, Oct 23, 2014 at 04:03:56PM +0530, akash.goel@xxxxxxxxx wrote: > > From: Akash Goel <akash.goel@xxxxxxxxx> > > > > > This is for improving the CPU write operation performance, as with such > > mapping, writes are almost 50% faster than with mmap_gtt. Also it avoids the > > I doubt it is the actual write that is faster. For example, > > gtt wc Operation > -------- ------ --------- > 424000.0 1.30 ShmPutImage 10x10 square > 29500.0 1.42 ShmPutImage 100x100 square > 1510.0 0.95 ShmPutImage 500x500 square Oops, bugs beware. I wasn't calling the ioctl correctly. Having re-run the test, I now get: gtt wc Operation -------- ------ --------- 424000.0 1.30 ShmPutImage 10x10 square 29500.0 1.44 ShmPutImage 100x100 square 1510.0 1.38 ShmPutImage 500x500 square Supporting your claims. Very nice. -Chris -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
