#noteToself #FreeBSD #OpenZFS #free_RAM_target
Roughly ~30-minute mark Allan Jude in ELI5: ZFS Caching (2019) presentation ("Turning the ARC",
https://youtube.com/watch?v=L_kBM_RHa6g&t=1794 )
mentions to adjust

# Lower (unit: byte);
vfs.zfs.arc.max,
# bit higher than default
# (unit: page; "hw.pagesize" MIB shows current byte/page in use).
vfs.zfs.arc_free_target

MIBs on low memory systems, say on a laptop.