I wrote: > A couple weeks ago, after we moved a user's home directory from a 5.7 box to 6.2, he came > to complain about slowness. > Unpack file from NFS-mounted directory to local disk, like /tmp, > everything's normal. cd to the NFS-mounted directory, and unpack it there, and it was > six to seven times slower. We repeated this a number of times, on a number of machines. At > first, we thought it was an NFSv4 issue, and I filed a bug with RedHat about it. > Then we did more testing; it seems to occur with 6.2; it's going to happen if that's got ext4. > However, my manager saw something else, just today: he noticed one of our nightly backup > servers was taking much, much longer to complete the rsync and delete. Then he saw that I'd > updated that backup server to 6.2, and after the backups started running again (probably > missing modules), they were taking a lot longer... about 6-7 times longer. As in going from > between .5 and 1 hr, to 5.5 to 9 hours. Well, I was googling on performance tuning NFS, and found <http://www.softpanorama.org/Net/Application_layer/NFS/nfs_performance_tuning.shtml>, where the author notes "One issue with migrating to NFSv4 is that all of the filesystems you export have to be located under a single top-level exported directory. This means you have to change your /etc/exports file and also use Linux bind mounts to mount the filesystems you wish to export under your single top-level NFSv4 exported directory." I makes a *real* difference. I tested it, on one 6.2 server, mounting a foo directory I created in the usual 3 levels deep, and another, /tmp/foo1, and doing my same unpack ran at 2/3rds the time. Not good - 6.5 min vs. 1+min for 5.7 & NFS3, but better. This alone suggests we need to go back to NFS 3 - it would be a Big Deal to relocate everyone's home directory. Doing a yum list \*nfs\* shows something called sblim-cmpi-nfsv3.x86_64. >From the info, I can't tell if I can just drop it in and run that, or if I'd have to yum remove nfs-utils & nfs-utils-lib. Anyone have a clue? mark