[Bug 42035] no way to turn off vsync

[Michal Suchanek]

2011/10/27 Michal Suchanek <hramrach at centrum.cz>:
> 2011/10/25 Michel Dänzer <michel at daenzer.net>:
>> On Mon, 2011-10-24 at 23:23 +0200, Michal Suchanek wrote:
>>> 2011/10/24 Michel Dänzer <michel at daenzer.net>:
>>> > On Mon, 2011-10-24 at 16:25 +0200, Michal Suchanek wrote:
>>> >> 2011/10/24 Michel Dänzer <michel at daenzer.net>:
>>> >> > On Mon, 2011-10-24 at 14:00 +0200, Michal Suchanek wrote:
>>>
>>> >> I am asking this because my experiments with glxgears  without the
>>> >> patch show vrefresh limited fps, fps unlimited by vrefresh, and 0 fps
>>> >> depending on some variables like what screen the window is on, if the
>>> >> window is mapped or not,
>>> >
>>> > Sounds like issues with determining which CRTC to synchronize to.

There are more strange things.

First, swapping the screen connections physically did not change the behaviour.

I don't think the crtcs would get swapped too but I am not sure.

The primary screen is not rotated, the secondary is.

Window last mapped on primary screen (or the secondary when I turn off
rotation) keeps capped by the screen refresh rate when unmapped.
Window last mapped on rotated screen is not capped when unmapped.

It seems that screen blank behaves like unmap, at least for glxgears.
Since the screen no longer paints and the gears are synchronized to
the screen after unmapping they sometimes stop painting too.

Thanks

Michal