Hi Robert, Are the different threading models the same between windows and linux? I remember seeing that windows osg (probably producer) didn't support thread per context before.
Zach -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Robert Osfield Sent: Tuesday, February 06, 2007 12:16 To: osg users Subject: [osg-users] Re: Names for different threading models Hi All, On 2/6/07, Robert Osfield <[EMAIL PROTECTED]> wrote: > 1) SingleThreaded - this is an easy one ;-) > 2) RenderingThreadPerContext or CullDrawThreadPerContext > 3) DrawThreadPerContext > 4) CullThreadPerCameraDrawThreadPerContext > > Does this make sense given the above? Is an long winded name for > option 4 sensible? Wow, popular thread... What I have gone for is: enum ThreadingModel { SingleThreaded, CullDrawThreadPerContext, DrawThreadPerContext, CullThreadPerCameraDrawThreadPerContext, AutomaticSelection }; Is there ideal set up of names? If not please ping me with your suggestions. I have changed the default ThreadingModel to AutomaticSelection, and this calls the new method Viewer::suggestThreadingModel() to set the final threading model used. This method will look at how many CPU cores you have available and how many windows you have and try to choose the best threading model to run. Expect single CPU single window apps to use SingelThreaded, dual core CPU single window apps to use DrawThreadPerContext, multiple CPU + multiple GPU <= num cores to use the CullThreadPerCameraDrawThreadPerContext, otherwise CullDrawThreadPerContext or DrawThreadPerContext will be chosen in cases where you have multiple windows. The later "CullDrawThreadPerContext or DrawThreadPerContext" is something that I have not decided upon yet, CullDrawThreadPerContext will typically lead to lower frame latency, while DrawThreadPerContext's double buffer will lead to an extra frames latency but higher chance of hitting vsync. If you miss vysnc then you'll pay an extra frames latency anyway... So if there is any chance you are going to miss a frame DrawThreadPerContext is your man, while CullDrawThreadPerContext is best when you are sure you'll hit vsync. Right now I've opted for DrawThreadPerContext in the multiple window case. You can also set the threading model yourself. A word of warning. the CullThreadPerCameraDrawThreadPerContext model has been implemented and in testing I have found deadlocks that I haven't got to the bottom of yet. I don't have enough cores to properly test it either - I really need a 4 core, 2 GPU machine... Robert. _______________________________________________ osg-users mailing list osg-users@openscenegraph.net http://openscenegraph.net/mailman/listinfo/osg-users http://www.openscenegraph.org/ _______________________________________________ osg-users mailing list osg-users@openscenegraph.net http://openscenegraph.net/mailman/listinfo/osg-users http://www.openscenegraph.org/
