Hi all,

we are experiencing severe NFS performance problems. Small files seem to work OK, but the server becomes irresponssive when we write large files from the local disks to the NFS mount on the storage server, up to a point where we cannot even do a nomal ls.

the NFS storage is mounted in fstab with:
192.168.10.220:/data /mnt/data nfs rsize=9700,wsize=9700,hard,intr,async,proto=tcp,po rt=2049,timeo=5,retrans=3 0 0

network connection consists of two 10 Gbit cards in bond mode:

auto bond0
iface bond0 inet static
address 192.168.10.110
netmask 255.255.255.0
bond-mode 802.3ad
bond-miimon 1000
bond-lacp-rate 1
bond-slaves eth2 eth3
mtu 9700

server box: 32 core xeon / 512 GB memory and 1.7 GB internal SSDs
open-e box: 8 core xeon / 32 GB memory and 12x4TB sata disks on LSI controler

any ideas how to tackle this?