[OpenAFS] OpenAFS client memory usage

Baumann Niklaus (LOG) niklaus.baumann@psi.ch
Fri, 16 Oct 2009 15:45:10 +0200

I have some questions about how OpenAFS 1.5.6400 works with RAM on
Windows XP (SP2/SP3):
While copying data from/to AFS, the afsd_service.exe increases it's
working set and fills the cachefile (at least fs getcacheparms tells).
On a client with a cache file of 384MB and 3GB RAM the "mem usage" in
Task manager then grows to ~440MB and won't shrink until I either
restart the service or start to run out of physical memory. I assume the
VMM then tells the afsd_service to cleanup (correct?). While this isn't
a problem on a client with 3GB of RAM it is indeed on older hosts with
say 512MB of RAM. On such a client I experience paging when copying
As far as I understood the afs clients works with the cache using a
memory mapped file and opens views onto this file while using the cache.
This views are then kept/cached in memory.
Shouldn't the AFS client flush the contents to the disk periodically and
close some of the views in order to release the memory again? Or is
there a way to tell AFS to keep only e.g. 64MB of the cachefile in
Maybe we just missed something to configure. Or is there a
recommendation for the cache file size in conjunction with amount of
physical memory installed? At the moment we plan to workaround this
effect by leaving the cache file size at the default value for all
clients we distribute AFS to.
Thanks for your hints,