On Mon, 2002-02-18 at 19:18, Zdenek Kabelac wrote: > > I believe this is what is going on: > > Movie players usually wait for for XFree operation completition by calling > XSync. Thus when XSync returns to the user space program there is assumption > that all XFree operation has been finished and player continues with > handling another frame. > > However for now it looks like XFree is actually returning sonner than > all pending operations (image transfers) are finished - as mplayer > is waiting in this stage then usually nothing tragical will happen > as long as you have fast enough CPU so mplayer could wait enough time > before it will decide it's about right time to decode next frame. > (might be simulated in aviplay as well - but as avifile has some > threaded prechaching it will show this behaviour instantly and you > do not have to turn on any postprocessing level). > > Aviplay almost immeditally after return from XSync call > wakes up decoding thread - if all the memory transfers would be > finished by this time everything would be just fine - however > if the Xserver is still transfering the memory then there will be > noticable slowdown as both operation will be completed slower then > they could be if these operation would be running in serial. > > Quit noticable is this on SMP machine where XFree is accessing memory > at the same time as decoder is decoding next frame.
But I still don't understand why _X_ should hog the CPU: - Without DRI, XvShmPutImage() itself only returns after it has memcpy()'d the data - With DRI, it might be possible that XSync doesn't really wait for the DMA transfer to complete (maybe PutImage should set info->accel->NeedToSync ?), but then it would be the graphics chip still accessing RAM, not X I'm very curious what the solution for this is gonna be. :) -- Earthling Michel Dänzer (MrCooper)/ Debian GNU/Linux (powerpc) developer XFree86 and DRI project member / CS student, Free Software enthusiast _______________________________________________ Dri-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/dri-devel
