This applies:
commit c4ede65bdf
Author: Mateusz Guzik <mjguzik@gmail.com>
Date: Fri Oct 30 23:26:10 2020 +0100
zstd: track allocator statistics
Note that this only tracks sizes as requested by the caller.
Actual allocated space will almost always be bigger (e.g., rounded up to
the next power of 2 or page size). Additionally the allocated buffer may
be holding other areas hostage. Nonetheless, this is a starting point
for tracking memory usage in zstd.
from openzfs