Bad performance after the threading model change

Hi EveryOne,

At the first commit of v0.93 (after the release of v0.92), there is a "Merge the 3 threading models into a single one". 753eef83

Has anybody made before/after performance tests at this change?

Because the memory usage seems to be ~50% more (850 Mb vs. 1250 Mb at 4K/10-bit content) and sometimes the CPU load is also higher with ~10% (55% vs 60% at 4K/8-bit content), comparing the libdav1d 0.92 final and the 0.93 first commit with the new threading model.

I use libdav1d and FFmpeg 4.4.1 static x64 builds with my video player application, on Windows 10, with a Core i7 CPU, probably AVX2 compatible.

The programatic difference can be that the FFmpeg lib uses unique thread number calculation/configuration at the older libdav1d (in libavcodec/libdav1d.c), which seems to be better than the new libdav1d internal code.