We have a server with A LOT of files in some directories (an email
server in maildir format).
Since we upgraded from OpenBSD amd64 7.3 to 7.5 (passing through 7.4) it
became very very very slow to access these large directories!
Up to 7.3 we used the following sysctl settings and everything was ok:
vfs.ffs.dirhash_maxmem=100000000
vfs.ffs.dirhash_dirsize=1024
But now, with 7.5, vfs.ffs.dirhash_dirsize no longer exists!
Only vfs.ffs.dirhash_maxmem and vfs.ffs.dirhash_mem exist, but it's not
clear how we can use them.
For example, according to "man 2 sysctl" vfs.ffs.dirhash_mem is NOT
Changeable, but we were able to change it!
But it is not clear what it is for...
Anyway, the question is: under OpenBSD 7.5, how can we improve the
access to directories with A LOT of files (normal FFF2 filesystem)?
We already increased the usage of cache memory with
"kern.bufcachepercent=80", but it's not enough.
Thanks.
