[Libva] Disabling sync on vblank

[Yann Dirson]

Yes, setting SwapbuffersWait off does the trick. Thanks!

2016-06-27 7:06 GMT+02:00 Ratin <ratin3 at gmail.com>:
> Shouldn't adding SwapbuffersWait parameter in /etc/X11/xorg.conf work?
>
> Section "Device"
>    Option "SwapbuffersWait" false
>    Identifier  "Card0"
>    Driver      "intel"
>    BusID       "PCI:0:2:0"
> EndSection
>
> - Ratin
>
> On Sun, Jun 26, 2016 at 8:46 AM, Xiang, Haihao <haihao.xiang at intel.com>
> wrote:
>>
>>
>> Hi Yann,
>>
>> vaPutSurface() is calling  DRI2SwapBuffers on X11 to display the image,
>> the behavior is controlled by  display server. You may check
>> xf86-video-intel for how is DRI2SwapBuffers implemented.
>>
>> Thanks
>> Haihao
>>
>>
>> >-----Original Message-----
>> >From: Libva [mailto:libva-bounces at lists.freedesktop.org] On Behalf Of
>> > Yann
>> >Dirson
>> >Sent: Sunday, June 26, 2016 11:11 PM
>> >To: libva at lists.freedesktop.org
>> >Subject: [Libva] Disabling sync on vblank
>> >
>> >Hello,
>> >
>> >When I'm decoding a video (using i965-va-driver, libva 1.7.0) and
>> >displaying frames using
>> >vaPutSurface, it looks as if the latter was syncing on vblank: i
>> >observe the frame rate of my
>> >program to be exactly that of the video mode refresh.
>> >
>> >I would like to test if we can do triple-buffering rather than sync on
>> >vblank, and see the
>> >influence on the result.
>> >
>> >It does not look like any parameter honored by other software pieces
>> >(Option VSync of the X intel
>> >driver, XV_SYNC_TO_VBLANK, glx's vblank_mode) has any influence.
>> >I cannot find any explicit reference to vsync or vblank in the libva
>> >or va-driver source code,
>> >and at first read (followed Broadwell path, admitedly quickly) it is
>> >not obvious that the
>> >intel-vaapi-driver exlicitly requires any synchro.  Can anyone shed some
>> > light ?
>> >
>> >Best regards,
>> >--
>> >Yann
>> >_______________________________________________
>> >Libva mailing list
>> >Libva at lists.freedesktop.org
>> >https://lists.freedesktop.org/mailman/listinfo/libva
>> _______________________________________________
>> Libva mailing list
>> Libva at lists.freedesktop.org
>> https://lists.freedesktop.org/mailman/listinfo/libva
>
>



-- 
Yann Dirson <yann at blade-group.com>
Blade -- 90 avenue des Ternes, 75017 Paris