[OpenAFS] OpenAFS client tuning for Maildir access

Linus Widströmer linus.widstromer@it.su.se
Tue, 26 Oct 2010 10:32:42 +0200

Hi everyone,

lately we have been focusing on tuning our afs fileservers as a part of
our ongoing AFS refurbishing work. Our main focus has been our email
system where we store loads of Maildirs in AFS, thus generating a
continuous load on both clients and fileservers. When we monitored the
clients we noticed numbers of noBuffers as well as lost callbacks, hence
we had a rationale for starting to look into client tuning as well as
server ditto. 

The client parameters which we have been focusing on are -stat,
-daemons, -rxpck and -files. 

Judging from the Git repo the default settings for these parameters
haven't been modified since 2003. Are the default values still
reasonable for a vanilla system or should they be updated? 

Are there any drawbacks of raising the number of daemons and rxpackets
all over the line of clients? We would prefer to run all clients with
the same set of config, rather than having to classify them as "high
load server", "medium load servers", "low load workstations" etc. 

Any pointers to documents or experiences of running maildirs in AFS
w.r.p. performance and availability are of course welcome. 

Best regards,
Linus Widströmer