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artem.jackson

Member

Registered: 2014-09-06

Posts: 22

[Solved]NVIDIA with primusrun slower then integrated Intel ?!

$ vblank_mode=0 primusrun glxspheres64 
OpenGL Renderer: GeForce GT 620M/PCIe/SSE2
180.209469 frames/sec - 201.113767 Mpixels/sec

 $ vblank_mode=0 glxspheres64 
OpenGL Renderer: Mesa DRI Intel(R) Ivybridge Mobile 
215.091464 frames/sec - 240.042073 Mpixels/sec

HOW ?!?!?

Last edited by artem.jackson (2015-01-20 09:26:20)

Gusar

Member

Registered: 2009-08-25

Posts: 3,605

Re: [Solved]NVIDIA with primusrun slower then integrated Intel ?!

Primusrun has overhead in copying frames from the virtual display to the actual display. You have a very low end Nvidia card and this overhead decimates performance so much the whole thing ends up slower than using the Intel GPU which has no such overhead. Primusrun is still basically a hack, not a proper Optimus solution.

It's also possible that because glxspheres is so simple, this overhead plays a much bigger role than with something more demanding of the GPU. Try a proper demo or an actual game, you might see a different picture then.

AnAkkk

Member

Registered: 2014-03-03

Posts: 148

Re: [Solved]NVIDIA with primusrun slower then integrated Intel ?!

It's the same for me, but in games it is totally different, I have a much better performance with the Nvidia card. You shouldn't use glxspheres/glxgears to mesure performance.

artem.jackson

Member

Registered: 2014-09-06

Posts: 22

Re: [Solved]NVIDIA with primusrun slower then integrated Intel ?!

see the topic https://bbs.archlinux.org/viewtopic.php?id=192446
marked as solved.