Re: head node has an extremely high load average.

Jonathan Billings <[email protected]>
Newsgroups gmane.linux.redhat.general
Message-ID <CACxoJuUUWPdvNUR7py=+3QQk=RvN+VYH1RA8O2EZQd0cyaxMKQ@mail.gmail.com>
I saw a 'gmetad' running on your head node, which means you're running
ganglia.  You can probably monitor your NFS traffic client-side on each
node and have ganglia collect that information.

Just keep in mind, your CPU load doesn't look that unusual for a NFS server
with many nodes running jobs writing to it.  You said you had 10 nfsd
threads, and your top output above said there were 3 tasks running on a
2-core system, with a load average between 13 and 14.  Sounds about right.
Don't focus on the load average, you'd be better off trying to improve
storage and network speed.

For example, I suggest installing the 'tuned' package and enable the
'enterprise-storage' profile (with tuned-adm).  That will change the
scheduler elevator algorithm as well as a bunch of sysctl items to
something optimized for storage.


On Thu, Jun 27, 2013 at 9:48 AM, Doll, Margaret Ann <[email protected]
> wrote:

> Thanks.  This sounds like what I need.
>
> On Thu, Jun 27, 2013 at 9:44 AM, Miner, Jonathan W (US SSA) <
> [email protected]> wrote:
>
> >
> > > How does one determine from which node the massive io requests are
> > coming?
> >
> > This falls under network monitoring.  You could use a program like
> > "iptraf"; if you run it on the server you should be able to get it to
> > display bytes per client, etc.
> >
> > Or if your switches have snmp monitoring, you could use mrtg to graph the
> > per port usage.  Assuming that each port maps to a single device, then
> > you'd be able to map high usage back to the client machine.  You could
> also
> > use a snmp monitoring program (Nagios is one...)  to actively alert you
> if
> > usage was above a certain threshold.
> >
> > https://fedorahosted.org/iptraf-ng/
> > http://oss.oetiker.ch/mrtg/
> > http://www.nagios.org/
> >
> > - Jon
> >
> > --
> > redhat-list mailing list
> > unsubscribe mailto:[email protected]?subject=unsubscribe
> > https://www.redhat.com/mailman/listinfo/redhat-list
> >
> --
> redhat-list mailing list
> unsubscribe mailto:[email protected]?subject=unsubscribe
> https://www.redhat.com/mailman/listinfo/redhat-list
>



-- 
Jonathan Billings <[email protected]>
College of Engineering - CAEN - Unix and Linux Support
-- 
redhat-list mailing list
unsubscribe mailto:[email protected]?subject=unsubscribe
https://www.redhat.com/mailman/listinfo/redhat-list
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.