[Linux-cluster] slow NFS performance on GFS2

[Barry Brimer]

>>> Hello,
>>> 
>>> I've installed a two nodes GFS2 cluster on Debian 7. The nodes are
>>> connected to the datas by iSCSI and multipathing with a 10 Gb/s link. I
>>> can write a 1g file with dd at 500 Mbytes/s. I export with NFS (on a 10
>>> Gb/s network) and I only can reach  220 Mbytes/s. I think that it's a
>>> little bit far from 500 Mbytes/s...
>>> 
>>> Do you how to tune my settings to increase the speed for NFS ?
>>> 
>>> GFS2 mount :
>>> /dev/vg-bigfiles/lv-bigfiles /export/bigfiles gfs2
>>> _netdev,nodiratime,noatime 0 0
>>> 
>>> NFS export :
>>> /export/bigfiles
>>> 172.16.0.0/16(fsid=2,rw,async,no_root_squash,no_subtree_check)
>>> 
>>> mount on NFS clients :
>>> nfs-server:/export/bigfiles /data/bigfiles nfs4
>>> _netdev,rw,user,nodiratime,noatime,intr 0 0

Fedora 19 contains a program called nfsometer which might be helpful in 
NFS tuning.