dirhash default maxmem and reclaimage values

[Robert Burmeister]

   Would people with experience tuning dirhash check the list[1]
   http://freebsd.1045724.n5.nabble.com/Suggest-changing-dirhash-defaults-
   for-FreeBSD-9-2-td5839351.html
   and contribute any benchmarks that they have that are more recent than
   2008?
   In question are:
   should vfs.ufs.dirhash_reclaimage be increased, if so what to?
   should vfs.ufs.dirhash_maxmem scale with kernel memory rather than RAM?
   (Autotuning maxmem on low RAM machines makes maxmem too small,
    and on large RAM machines scavenging 10% of maxmem on vm_lowmem events
   becomes too aggressive.)

References

   1. http://freebsd.1045724.n5.nabble.com/Suggest-changing-dirhash-defaults-for-FreeBSD-9-2-td5839351.html