On Tue, Dec 14, 2010 at 7:41 PM, Steve Satterfield <[email protected]> wrote:
> Hi Tim, > > I have pulled your questions out of the body of the test and responding to > them up front. > > >> It is paradoxical. That it works at all is do to the fact that, with >> vsync enabled, all GPU activity is buffered up until the after the >> next SwapBuffers call. >> > > I am not entirely clear what you mean in this statement. I will say > that for the majority of our testing, we have the Nvidia environment > variable "__GL_SYNC_TO_VBLANK" set to 0 so the swap is tied to > vblank. I believe this is specific to the Nvidia driver. For normal > production its set to 1. The X/N performance is observed in both > cases. > > > I was referring to OSG_SERIALIZE_DRAW_DISPATCH=ON. It's hard to believe that it could result in a better frame rate unless you know that the actual GPU operations happen well after the calls to OpenGL. But that is orthogonal to the matter of this bug... > > I put together a multicard system specifically to look at these >> issues, and I too am very interested in getting it to work. >> > > Does this mean you are seeing performance problems like I have > described on your system? We would certainly be interested in > hearing how our test program(s) run on your multi-card system. > Yes, I have a dual GTX 460 system, and I've seen the phenomenon. These are not Quadro cards so I have limited expectations on synchronization, but I do expect the same performance as a single card system. Tim
_______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
