Mir Now Has Improved Multi-Monitor Synchronization

[phoronix]

Phoronix: Mir Now Has Improved Multi-Monitor Synchronization

One day after Canonical developers landed Mir composite bypass support to dramatically improve the performance of full-screen games on Mir/XMir, Mir has picked up another important feature...

http://www.phoronix.com/vr.php?view=MTQ0OTU

[jakubo]

so when you have one 60Hz and on 80Hz Monitor you apply 80Hz synch to the 60Hz aswell? resulting in a nasty line at about 3/4 th of the screen with the 60Hz? or how does it work? is there no way for asynchroneous uplink? is it due to the feature of one combined surface over all the monitors...?
safest way would probably be refreshing at 20Hz.... if there was no monitor with 70Hz XD

please help me understand

[dh04000]

so when you have one 60Hz and on 80Hz Monitor you apply 80Hz synch to the 60Hz aswell? resulting in a nasty line at about 3/4 th of the screen with the 60Hz? or how does it work? is there no way for asynchroneous uplink? is it due to the feature of one combined surface over all the monitors...?
safest way would probably be refreshing at 20Hz.... if there was no monitor with 70Hz XD

please help me understand

I am most likely wrong on this but, I think this edit will help.

"to the highest refresh rate (shared by) all monitors is being used by Mir for determining synchronization."

So if one monitor supports 60Hz and the other supports 120Hz and 60Hz, then it will sync to 60Hz for both.

[agd5f]

The only way to avoid tearing on multiple displays is to synchronize each display separately. Even if the displays are running at the same refresh rate, there is no guarantee that both vblank periods will be lined up.