[Bug 106175] amdgpu.dc=1 shows performance issues with Xorg compositors when moving windows

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=106175

grmat at sub.red changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |grmat at sub.red

--- Comment #22 from grmat at sub.red ---
Created attachment 140858
  --> https://bugs.freedesktop.org/attachment.cgi?id=140858&action=edit
GALLIUM_HUD showing stuttering

I can confirm the issue.

Having a Radeon R9 290X (Hawaii XT), DC introduces heavy stuttering on a
composited X desktop while interacting with the window manager. This stuttering
can't be resolved by forcing high power states.

Attached is a screenshot to give an impression of the stuttering.
Top left is the GALLIUM_HUD with the compositor's frame rate and frame time
graph. On the right, there is Firefox with the page
https://testufo.com/photo#photo=quebec.jpg&pps=960&pursuit=0&height=0 having
hardware acceleration force-enabled and also showing fps/frametime graphs. The
web page has continuous movement, ensures that there is a screen update every
frame and makes it easy to detect stutter.
This looks perfectly fine and the graphs represent that as well.
On the bottom there is the same setup but while changing window focus or moving
a third window around. Firefox stutters as hell (suspecting vsync stuttering)
and the graphs show that as well.

Disabling DC resolves the issue completely and the bottom scenario would look
and feel the same as the upper one with DC.

In this current situation, I could disable DC and have a smooth desktop at the
cost of several dozens of watts idle power or save power and use a stuttering
desktop with DC enabled.

-- 
You are receiving this mail because:
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/dri-devel/attachments/20180727/57dd04e0/attachment.html>