More 16 vs 24 bpp profiling
jordan.crouse at amd.com
Tue Sep 11 11:29:44 EDT 2007
On 11/09/07 13:05 +0200, Stefano Fedrigo wrote:
> I've done some more profiling on the 16 vs. 24 bpp issue.
> This time I used this test:
> A simple speed test: I measured the time required to scroll down and up
> one time all the generated list. Not extremely accurate, but I repeated the
> test a few times with consistent results (+- 0.5 secs). Mean times:
> xserver 1.4
> 16 bpp: 37.9
> 24 bpp: 40.7
> xserver 1.3
> 16: 46.4
> 24: 50.1
> At 24 bpp we're a little slower. 1.3 is 20% slower than 1.4. The pixman
> migration patch makes the difference: 1.3 spend most of that 20% in memcpy().
> The oprofile reports are from xserver 1.4. I don't see much difference
> between 16 and 24, except that at 24 bpp, less time is spent in pixman and more
> in amd_drv. At 16 bpp pixman_fill() takes twice the time.
> Unfortunately without a working callgraph it's not very clear to me what's
> happening in amd_drv. At 24bpp gp_wait_until_idle() takes twice the time...
What can we do to fix this? I would really like to know who is calling
Also, I think we're spending way too much time in
gp_color_bitmap_to_screen_blt() - is there any way we can get more indepth
profiling in that one function?
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