On Wed, Dec 10, 2008 at 12:07 PM, Davide Cittaro davide.cittaro@ifom-ieo-campus.it wrote:
Hi all, I'm migrating from Gentoo to CentOS... I'm experiencing a rather low performance in NFS r/w (as client). NFS server is solaris (which exports zfs volumes via nfs). The very same exports were mounted with the same parameters (auto,nosuid,exec) on gentoo and centos server (bot x86_64)... It happens that centos is 5-10 times slower either in read and write operations... Ok, I'll try to tune rsize and wsize, but does anybody have an hint on this low performance?
Which version of CentOS are you using? The upstream kernels have had issues at different points with NFS performance (the 2.6.18 had a bunch of problems that were fixed in 2.6.20-22 time frame and have had to be backported.. then there were changes and breakage somewhere after that.. ) I normally try a set of comparisons:
1) What does CentOS-4 do? What does CentOS-5 do? 4 may actually be faster than 5 in some cases due to switch/card issues. 2) Then there are issues with TCP, size of frames, etc...