Monday, September 4

NFS locking issues

Been quite busy at work, decommissioning some old servers.
We are trying to get rid of everything pre RHEL/CentOS 3.x. After buying a new shiny file server for our home directories (a Dell 2850 with lots of cheap disk space) I ran in to some very weird problems. Everything worked fine at first, I myself (as a XFCE user) didn’t have any problems at all, but our GNOME users ran it some serious problems. When logging in to GNOME the desktop did not start properly, gnome-panel looked like a grey bar without any tools and the desktop menu didn’t appear on right click. Simply, nothing in GNOME worked. Not in Centos, not in Fedora, not even JDS in Solaris worked.
After installing the GNOME debuginfo packages for Linux it appeared to be some weird NFS locking problem (haven’t we all hear that one before) in gconfd. NLM auth lock calls got denied. Hard to troubleshoot why and how at the time, we simply remounted the NFS shared with the nolock mount option in Linux and the sort of undocumented mount option llock in Solaris.
NFSv3 is just a mostly irritating patch work of addons, statd, lockd etc etc.
Hate NFSv3, why didn’t I include a NFSv4 migration while we where at it.
The nolock "hack" will have to do for now, I’ll will try to troubleshoot the problem later on.

fstab line in Linux:
fs1:/export/home  /export/home nfs rsize=16384,wsize=16384,intr,nolock
I'll try to post some rather interesting Oracle 10gR2 Sun Fire T200 server benchmarks later on this week. I've found a rather good benchmarking tool called Swingbench. Written in Java and easy to use. It comes with a data loading utility to populate the database with nice bogus data and then has a few tools to simulate different workloads.
Been reading a lot about file system tuning recently as well, ext3 tuning parameters and Oracles filesystemio_options parameter, need to dig up a good test box for that so I can evaluate the options. My current two disk machine doesn't cut it for I/O load testing.

Finally a quick movie recommendation.
Bought a new LCD TV the other day so I've been overindulging in movies recently.


And a big thanks to Lukas Smith for sending me a few DVDs from my wish list.

1 comment:

Hubert Cross said...

"tack!" for this post, now my users' GNOME desktops have panels again.