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Ubuntu - Video - ffmpeg - Hardware Acceleration using GPU - AMD GPU - Benchmark

ffmpeg -hwaccel vaapi -hwaccel_device /dev/dri/renderD128 -hwaccel_output_format vaapi -i a.mp4 -c:v hevc_vaapi -q:v 28 -f null - -benchmark

returns:

...
bench: utime=0.156s stime=0.195s rtime=3.003s
bench: maxrss=358944kB

NOTE: The maxrss serves to indicate the maximum RAM used during the ffmpeg execution.

The utime, stime, rtime indicate accordingly:

user time;
- utime is the sum of processing time across all threads. Since they may operate in parallel, utime can exceed rtime.
system time;
real time.

The following parts of the command force a null file and tells ffmpeg to benchmark.