This is on an intel + radeon laptop, so I need to run encoding=
with gstreamer
with DRI_PRIME=3D1.
Here is an example video:
http://www.sample-videos.com/video/mp4/720/big_buck_bunny_720p_1mb.=
mp4
DRI_PRIME is doing a good job of waking up the GPU from runpm when needed f=
or
encoding via VAAPI and OMX, but for comparison I'll run glxgears both times.
I'm encoding the mentioned example video with VAAPI with this exact command:
$ time DRI_PRIME=3D1 LIBVA_DRIVER_NAME=3Dradeonsi gst-launch-1.0 -e filesrc
location=3Dbig_buck_bunny_720p_1mb.mp4 ! qtdemux ! h264parse ! avdec_h264 !=
queue
! videoconvert ! queue ! video/x-raw,format=3DNV12 ! vaapih264enc ! h264par=
se !
matroskamux ! filesink location=3Doutput.mkv
For low GPU stress I run the gst pipeline while glxgears with vsync is runn=
ing:
$ DRI_PRIME=3D1 glxgears
Result: 0.75s user 0.33s system 2% cpu 52.779 total
For higher GPU stress I run the gst pipeline while glxgears without vsync is
running:
$ DRI_PRIME=3D1 vblank_mode=3D0 glxgears
Result: 0.99s user 0.28s system 43% cpu 2.928 total
I also tried a very similar pipeline with OMX:
$ time DRI_PRIME=3D1 gst-launch-1.0 -e filesrc
location=3Dbig_buck_bunny_720p_1mb.mp4 ! qtdemux ! h264parse ! avdec_h264 !=
queue
! videoconvert ! queue ! video/x-raw,format=3DNV12 ! omxh264enc ! h264parse=
!
matroskamux ! filesink location=3Doutput.mkv
Low GPU stress: 0.96s user 0.24s system 19% cpu 6.298 total
High GPU stress: 1.10s user 0.24s system 141% cpu 0.949 total
Overall OMX encoding does a lot better, but it's still a large difference a=
nd
still below "real time" for the 5 second video.