Hi Jan, Am 18.06.2008 um 18:36 schrieb Jan Schulze: > > I did comparisons compiling gcc on the old and new systems while > running > tcpdump. I found, that the new systems performed a lot more NFS > lookups > (by factor ~4). Everything else seemed normal. > > File transfer to the NFS server is OK, no speed problems here. > Tcpdump, > however shows a lot of lines like this one, when copying files: > 18:19:56.571906 IP bsnode02.0 > morphin.nfs: 1448 null > > Load on the NFS server is much higher than before. I'm a little bit > at a > loss - how could I debug these issues further? This is a bug in the kernel seemingly caused by a weird combination of patches in the RHEL kernel. See (in order): http://bugs.centos.org/view.php?id=2635 https://bugzilla.redhat.com/show_bug.cgi?id=431092 https://bugzilla.redhat.com/show_bug.cgi?id=321111 We have encountered the same problems and switching to kernel 2.6.18-53.1.13.el5.bz321111 as reported in the CentOS bug tracking solved the problem for us. Kind Regards, Felix -- Dipl.-Ing. Felix Engel | mail: [log in to unmask] fon: +49 241 80 27629 | fax: +49 241 80 28306 RWTH Aachen University, SSS 611920, Templergraben 55, D-52056 Aachen