Comment=
# 7
on bug 98784<=
/a>
from Samuel Pitoiset
Can you try with LIBGL_DRI3_DISABLE=3D1 ? This will use DRI2 a=
nd it should fix
the flickering.
After bisecting, the first bad commit seems to be:
commit d3d33918c79d9e87aedaf6f70ed39f75eed262a0
Author: Michel D=C3=A4nzer <michel.daenzer@amd.com>
Date: Wed Aug 17 17:02:04 2016 +0900
loader/dri3: Overhaul dri3_update_num_back
Always use 3 buffers when flipping. With only 2 buffers, we have to wait
for a flip to complete (which takes non-0 time even with asynchronous
flips) before we can start working on the next frame. We were previously
only using 2 buffers for flipping if the X server supports asynchronous
flips, even when we're not using asynchronous flips. This could result
in bad performance (the referenced bug report is an extreme case, where
the inter-frame stalls were preventing the GPU from reaching its maximum
clocks).
I couldn't measure any performance boost using 4 buffers with flipping.
Performance actually seemed to go down slightly, but that might have
been just noise.
Without flipping, a single back buffer is enough for swap interval 0,
but we need to use 2 back buffers when the swap interval is non-0,
otherwise we have to wait for the swap interval to pass before we can
start working on the next frame. This condition was previously reversed.
Cc: "12.0 11.2" <mesa-stable@lists.freedesktop.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.c=
gi?id=3D97260
Reviewed-by: Frank Binns <frank.binns@imgtec.com>
Reviewed-by: Eric Anholt <eri=
c@anholt.net>
(cherry picked from commit 1e3218bc5ba2b739261f0c0bacf4eb662d377236)
Squashed with commit:
loader/dri3: Always use at least two back buffers
This can make a significant difference for performance with some extreme
test cases such as vblank_mode=3D0 glxgears.
Fixes: 1e3218bc5ba2 ("loader/dri3: Overhaul dri3_update_num_back&q=
uot;)
Cc: "12.0 11.2" <mesa-stable@lists.freedesktop.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.c=
gi?id=3D97549
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Tested-by: Dieter N=C3=BCtzel <Dieter@nuetzel-hh.de>
(cherry picked from commit dc3bb5db8c81e7f08ae12ea5d3ee999e2afcbfd1)
:040000 040000 aa5cf86f1e98d023f9539a6a15654fd9754101a2
fb92ad057feeb3fbff38d808c71c7e5e1cead9af M src