On Tue, 2010-10-12 at 18:45 +0100, Peter Clifton wrote: > Using glxgears as a tool to exercise the GPU with some simple rendering, > I have noted a strange cliff in the intel_gpu_top output when resizing > the glxgears window: > > Below a certain size e.g.: > > -geometry 576x868+0+29
> render busy: 21%: ████▎ > render space: 10/126976 (0%) > When I increase the window size just a fraction, to: > > -geometry 576x871+0+29 > The CS (command streamer) unit jumps to 100% busy, along with the render > busy graph. Does anyone have any ideas why? > > render busy: 100%: ████████████████████ > render space: 61/126976 (0%) It would appear that this transition occurs at the point when glxgears executed with vblank_mode=0 set, gives approx 60Hz (vblank rate). I can only presume therefore, that the command stream shows as 100% when it is stalling the CPU.. is that right? -- Peter Clifton Electrical Engineering Division, Engineering Department, University of Cambridge, 9, JJ Thomson Avenue, Cambridge CB3 0FA Tel: +44 (0)7729 980173 - (No signal in the lab!) Tel: +44 (0)1223 748328 - (Shared lab phone, ask for me) _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
