-
NFS hang
I have built a new system and the load right now if very small, but I having some serious performance issues.
I have a single linux box hooked up to the open-e using NFS. It is connected to 3 different shares. Every so often (can't find a pattern), the NFS seems to lock-up/hang for about a minute, meaning any read requests for that mount are queued. For example I am even unable to perform 'ls -la' on that directory until it come back again.
Nothing is reported in /var/log/messages on the linux box to suggest connection was lost. Running a ping reports no errors,a ll come back 0.2ms or so.
I mount the shares in fstab using default values as follows:
10.20.20.160:/data1 /data/data1 nfs defaults 0 0
10.20.20.160:/system /data/system nfs defaults 0 0
10.20.20.160:/logs /data/logs nfs defaults 0 0
These defaults give these settings:
[root@cnbflbs21 data1]# cat /proc/mounts | grep nfs
sunrpc /var/lib/nfs/rpc_pipefs rpc_pipefs rw 0 0
10.20.20.160:/data1 /data/data1 nfs rw,vers=3,rsize=524288,wsize=524288,hard,proto=tcp ,timeo=600,retrans=2,sec=sys,addr=10.20.20.160 0 0
10.20.20.160:/system /data/system nfs rw,vers=3,rsize=524288,wsize=524288,hard,proto=tcp ,timeo=600,retrans=2,sec=sys,addr=10.20.20.160 0 0
10.20.20.160:/logs /data/logs nfs rw,vers=3,rsize=524288,wsize=524288,hard,proto=tcp ,timeo=600,retrans=2,sec=sys,addr=10.20.20.160 0 0
Other info:
open-e = 5.0.DB49000000.3278
linux = CentOS 5.4 x64 (it is running as a guest on ESX 4)
RAID = RAID6, 3ware 9650SE, 15 x 1TB drives + 1 hot spare
-
Sorry I forgot to add:
When the "hang" is happening I can still access the actual files from a Windows box directly to the Open-E share, so I am pretty certain it's the NFS bit that is going wrong (at one end or another), not just a performance bottleneck.
Finally, the iostats on the open-e show very little activity, this box isn't busy
-
We did have an update for the NFS that might help though it was for this version of 3278 that it would hang or no access to the NFS protocol. Once this update was installed all is working ok. Another options would be to update to the latest version of DSS V5 to build 3518 as well. But read the release notes concerning the mount commend with NFS and the word "share".
