[CentOS] home directory server performance issues

Tue Dec 11 22:05:30 UTC 2012
Keith Keller <kkeller at wombat.san-francisco.ca.us>

On 2012-12-11, Dan Young <danielmyoung at gmail.com> wrote:
> On Mon, Dec 10, 2012 at 9:37 AM, Matt Garman <matthew.garman at gmail.com>wrote:
>
>> I?m looking for advice and considerations on how to optimally setup
>> and deploy an NFS-based home directory server.  In particular: (1) how
>> to determine hardware requirements, and (2) how to best setup and
>> configure the server.  We actually have a system in place, but the
>> performance is pretty bad---the users often experience a fair amount
>> of lag (1--5 seconds) when doing anything on their home directories,
>> including an ?ls? or writing a small text file.
>
> Just going to throw this out there. What is RPCNFSDCOUNT in
> /etc/sysconfig/nfs?

I was also bit by this issue after a recent migration.  The default in
CentOS 6 is 8, which was too small even for my group, which has only 10
or so NFS clients, and only a handful active at any one time.

It is easy to change the number of nfsd kernel threads on the fly: just
do

rpc.nfsd NN

where NN is the number of threads you want.  The kernel will adjust the
number of running threads on the fly.  If that solves your performance
issue, then you can adjust RPCNFSDCOUNT accordingly.

--keith


-- 
kkeller at wombat.san-francisco.ca.us