nfs issues

Jean-Christophe Ducom jducom at nd.edu
Mon May 6 12:05:41 PDT 2002


> Kelly,
>
> Make sure that you have enough nfsd processes running. By default
RH7.2
> only starts 4, if you are running on all 16, you want at least 16 nfsd

> processes, but you won't need more than 32. There is some overhead
> associated with these, so try to tune your numbers. Running out of nfs

> processes could be at least part of the problem.
>
> For example, I run 20 nfsd on a 16p Origin2000 and 20 on a 32p
Beowulf.

>From http://nfs.sourceforge.net/
5.3. Number of Instances of NFSD

Most startup scripts, Linux and otherwise, start 8 instances of nfsd. In
the early days of NFS, Sun decided on
this number as a rule of thumb, and everyone else copied. There are
no good measures of how many instances are optimal, but a more
heavily-trafficked server may require more. If you
are using a 2.4 or higher kernel and you want to see how
heavily each nfsd thread is being used, you can look at the file
/proc/net/rpc/nfsd. The last ten numbers on the
th line in that file indicate the number of seconds that the
thread usage was at that percentage of the maximum allowable. If you
have a large number in the top three
deciles, you may wish to increase the number of nfsd instances. This
is done upon starting nfsd using the number of instances as the command
line option. See the nfsd man page for
more information.

Those links are pretty good too to tune your nfs server:
http://www.linuxdoc.org/HOWTO/NFS-HOWTO/performance.html
http://www.princeton.edu/~unix/Solaris/troubleshoot/nfsstat.html

        JC







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