Alan, What are you using for backend storage? I did some minor tuning for my EVA8100 and went from 200MB/s to 550MB/s. Also, by default, plocks are set to some rediculously small number, 100 if I recall. You can rais or eliminate that limit fairly easy. That seems to help as well. If people know more about your hardware, it'll help in finding what knob to turn. -C <div class="gmail_quote">On Thu, Mar 4, 2010 at 2:33 PM, Alan A <<a href="mailto:alan.zg@gmail.com">alan.zg@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">We are trying to deploy GFS in production, and are experiencing major performance issues. What parameters in GFS settune can be changed to increase I/O, to better tune performance? Application we run utilizes a lot of I/O, please advise. We experience OK performance when starting, but as things ramp up and we get few processes going GFS slows dramatically. -- Alan A. -- Linux-cluster mailing list <a href="mailto:Linux-cluster@redhat.com">Linux-cluster@redhat.com</a> <a href="https://www.redhat.com/mailman/listinfo/linux-cluster" target="_blank">https://www.redhat.com/mailman/listinfo/linux-cluster</a> </blockquote></div>