Hi Ferdi, It sounds like the OpenGL driver is not behaviour well in your case and twisting the results from what you would normally expect. With scene of 25M polygons you are almost certainly GPU/bandwidth limited, and pretty likely that the OpenGL fifo is backing up and playing havoc. Multi-processing is this situation is not really going to make a huge difference in terms of potential gain because the bottleneck is elsewhere - you aren't CPU limited, it shouldn't make things worse, and the fact that it is suggests that the driver is having issues.
What are you cull/draw/gpu stats? Robert. On Thu, Dec 4, 2008 at 10:43 AM, Ferdi Smit <[EMAIL PROTECTED]> wrote: > I've been looking into thread/process affinity with respect to a dual-GPU > setup. This is what I found back then: > > 2 processes, CPU affinity on different cores, each renders the full scene on > a different GPU > > OSG_THREADING=SingleThreaded > (1 core shows heavy use, 2nd core show moderate use, 2 cores idle) > > Quadro 5600 8800GTX > Multi-GPU / Multi-Processing 16 15 (fps) > > OSG_THREADING=ThreadPerContext > (CPU Affinity is set but appears to be ignored: 1 core shows heavy use, > others idle) > > Multi-GPU / Multi-Processing 11 14 (fps) > > So, yes, it helps if the CPU load is balanced across cores, even for this > simple 25M polygon scene that is for 99% GPU. Also, OSG seems to mess up > manual settings when set to multi-threading :) Check CPU loads in the > performance monitor. Don't let 3 cores stand idle all the time; it's a waste > of available processing time, and this will only get worse in the future > with more cores. > > Side note, I finally received my 4GB memory, so I can get this quad core, > dual GTX260, pcie 2.0 machine running :) Let's see if it behaves differently > from a Quadro+8800 on pcie 1.1. > > Ulrich Hertlein wrote: >> >> Additionally: what is the communities' experience with manually assigning >> processes to cores? Does it work? >> >> It sounds like a good idea but in my experience it's best to leave the >> scheduling up to the operating system to handle core affinity (except when >> you're running Windows which has a completely fscked-up round-robin >> scheduler). >> >> Cheers, >> /ulrich >> _______________________________________________ >> osg-users mailing list >> osg-users@lists.openscenegraph.org >> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >> > > > -- > Regards, > > Ferdi Smit > INS3 Visualization and 3D Interfaces > CWI Amsterdam, The Netherlands > > _______________________________________________ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
