https://bugs.freedesktop.org/show_bug.cgi?id=94708
--- Comment #12 from Arthur Hrast Essenfelder arthur.essenfelder@gmail.com --- I am also facing a similar issue. I also get very low performance when using the DIS Card and the radeon driver in comparison with the IGD Intel card.
# vblank_mode=0 glxgears ATTENTION: default value of option vblank_mode overridden by environment. ATTENTION: default value of option vblank_mode overridden by environment. 35719 frames in 5.0 seconds = 7143.730 FPS 35715 frames in 5.0 seconds = 7142.853 FPS 34593 frames in 5.0 seconds = 6910.545 FPS
# DRI_PRIME=1 vblank_mode=0 glxgears ATTENTION: default value of option vblank_mode overridden by environment. 8298 frames in 5.0 seconds = 1659.484 FPS 8313 frames in 5.0 seconds = 1662.389 FPS 8315 frames in 5.0 seconds = 1662.897 FPS
I posted this issue a few days ago on ask.fedoraproject.org but so far no luck: https://ask.fedoraproject.org/en/question/87235/low-performance-when-using-t...
In any case, I think this is the best place to seek help. Here are more details on my system:
Distributor ID: Fedora Description: Fedora release 23 (Twenty Three)
# lspci | grep VGA 00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09) 01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Whistler [Radeon HD 6730M/6770M/7690M XT]
# cat /sys/kernel/debug/vgaswitcheroo/switch 0:IGD:+:Pwr:0000:00:02.0 1:DIS: :Pwr:0000:01:00.0
# glxinfo | grep "OpenGL renderer" OpenGL renderer string: Mesa DRI Intel(R) Sandybridge Mobile
# DRI_PRIME=1 glxinfo | grep "OpenGL renderer" OpenGL renderer string: Gallium 0.4 on AMD TURKS (DRM 2.43.0, LLVM 3.7.0)
# Xorg -version X.Org X Server 1.18.3