Comment 1 Olivier Fourdan 2019-07-02 08:24:47 CEST

Xpresent or GLX?

I don't know, default.

Comment 3 Olivier Fourdan 2019-07-02 08:30:28 CEST

Which driver, intel or modesetting?

Rather intel driver.

Comment 5 Olivier Fourdan 2019-07-02 09:06:18 CEST

Have you tried with the modesetting driver instead? (this is default, the intel driver hasn't got any release in years, 2.99.997 was tagged 5 years ago).

xfwm4 relies on either GLX or Xpresent to swap buffers on vsync, if you get tearing, there is not so much it can do.

That said, this could be simply that the two outputs have completely different refresh rates and the driver cannot sync on both simultaneously, you could try changing the refresh rates of your monitors to be closer to see if that makes any difference.

In any case, it works for me, tear free in multi monitor setup on intel (using the modesetting driver), with both Xpresent (with https://gitlab.freedesktop.org/xorg/xserver/commit/6e199e46) and GLX, tested on a few laptops.

I'm not sure which driver I have, but this tearing is something new, I observed it about 1 or 2 weeks ago, before was ok.

I'm not sure which driver I have, but this tearing is something new, I observed it about 1 or 2 weeks ago, before was ok.

Comment 8 Olivier Fourdan 2019-07-02 14:34:58 CEST

Could be https://gitlab.freedesktop.org/xorg/xserver/issues/839

Graphics:  Device-1: Intel Xeon E3-1200 v2/3rd Gen Core processor Graphics driver: i915 v: kernel 
           Display: x11 server: X.Org 1.20.5 driver: intel unloaded: modesetting resolution: 1920x1200~60Hz, 1920x1200~60Hz 
           OpenGL: renderer: Mesa DRI Intel Ivybridge Desktop v: 4.2 Mesa 19.0.6

Comment 10 Git Bot 2020-05-29 12:27:07 CEST

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