[OpenAFS] need help tuning openafs

Wes Chow wes@woahnelly.net
Fri, 3 Sep 2004 18:43:10 -0400


whoops, forgot to hit "reply to all"...


> > >I'm playing with a few of the 45 gig machines now and I've noticed
> > >that afsd startup times are unacceptably long.  I took the advice from
> > >the AFSLore wiki and used "afsd -chunk 17", however just starting afsd
> > >on a clean /var/cache/openafs directory takes 20-30 minutes.  On an
> > >already populated cache directory, it takes maybe 3 or 4 minutes.
> > >After it's done, afs_cachetrim runs 80-90% cpu for an unkown period of
> > >time.  (I have yet to see one finish, and it's been close to 2 hours).
> > 
> > It has to populate the cache, the first time, and scan it on subsequent 
> > boots, and presumably whichever filesystem you're using for the cache has 
> > slow access times.
> 
> Is the subsequent scanning what afs_cachetrim does?  The second time
> it boots, afsd only takes a few minutes to start so it's not so bad.
> What's really killing me is the fact that afs_cachetrim hasn't
> finished yet and is hogging so much CPU.
> 
> Is the time it takes to finish proportional to the number of chunks?
> I've even tried chunk sizes of 2^30, but that doesn't seem to make
> much difference...
> 
> Wes