[oglop@t450s]$ vblank_mode=0  glxspheres64
Polygons in scene: 62464 (61 spheres * 1024 polys/spheres)
ATTENTION: default value of option vblank_mode overridden by environment.
ATTENTION: default value of option vblank_mode overridden by environment.
Visual ID of window: 0x20
Context is Direct
OpenGL Renderer: Mesa DRI Intel(R) HD Graphics 5500 (Broadwell GT2)
183.579885 frames/sec - 204.875151 Mpixels/sec


[oglop@t450s]$ vblank_mode=0 optirun glxspheres64
Polygons in scene: 62464 (61 spheres * 1024 polys/spheres)
Visual ID of window: 0x20
Context is Direct
OpenGL Renderer: GeForce 940M/PCIe/SSE2
76.068009 frames/sec - 84.891898 Mpixels/sec
77.826314 frames/sec - 86.854166 Mpixels/sec



[oglop@t450s]$ vblank_mode=0 optirun -b primus  glxspheres64
Polygons in scene: 62464 (61 spheres * 1024 polys/spheres)
ATTENTION: default value of option vblank_mode overridden by environment.
ATTENTION: default value of option vblank_mode overridden by environment.
Visual ID of window: 0x20
Context is Direct
OpenGL Renderer: GeForce 940M/PCIe/SSE2
ATTENTION: default value of option vblank_mode overridden by environment.
ATTENTION: default value of option vblank_mode overridden by environment.
91.711972 frames/sec - 102.350561 Mpixels/sec
91.697643 frames/sec - 102.334569 Mpixels/sec