Slow perf with uridecodebin (sysmem) and glimagesink with 4K60 HDR10 content
I think the issue is that uridecodebin doesn't negotiate caps with DMA modifiers, and the VA decoders output software buffers that are then re-uploaded (SLOW!) using glupload by glimagesink. There's no issue with uridecodebin3.
Because the VA decoders are PRIMARY+1 now, older applications might suddenly see unusable performance.
Test file: 4K60_HDR10.mkv
slow: uridecodebin uri=file://$PWD/4K60_HDR10.mkv ! glimagesink
or gst-play-1.0 4K60_HDR10.mkv
fine: uridecodebin3 uri=file://$PWD/4K60_HDR10.mkv ! glimagesink
On AMD systems this actually segfaults, which is probably a bug in glupload?: #2935 (closed)
Marking as a regression because this is getting auto-plugged now.
Interestingly, the same issue also happens with software decoders. Perf is good-enough with xvimagesink (buffers aren't late), although the output seems to be dropping some frames.