[OpenAFS] Re: Tuning the client and server

Andrew Deason adeason@sinenomine.net
Mon, 28 Jan 2013 16:05:02 -0600

On Mon, 28 Jan 2013 12:58:17 -0800
Timothy Balcer <timothy@telmate.com> wrote:

> I am looking at afsmonitor on the client involved, and I am seeing a
> large number of vcache misses in afsmonitor (519000 misses vs 6251
> hits, at the moment).

Based on the rest of your email, I assume you know which files/accesses
are generating those hits and misses.

Do you know how frequently you are accessing these files? How many
clients would be reading/stat'ing them at around the same time? Do these
files ever change?

> The product of dcache and chunksize is equal to less than 95% of the
> cache partition size, which is 5 Gigabytes. I am not dealing with
> loads of volumes at once in these operations... two to four at a time.

-dcache just sets the number of in-memory dcache entries, not the number
of chunks for the whole cache. The afsd manpage makes a few references
to multiplying the dcache and chunksize together, but that's for a
memory cache. I don't think you want to set -dcache; I would just
configure the cache size and the chunksize if you want.

Andrew Deason