NFS Optimization

Server Side

/etc/exports

/mnt/raid5 192.168.15.142/32(rw,async,no_root_squash)

async - dramatic throughput increase, but dangerous if a client does not unmount cleanly..

Tuning /etc/sysctl.conf

      net.core.rmem_default = 262144
      net.core.rmem_max = 262144
      #
      # Increase the fragmented packet queue length
      net.ipv4.ipfrag_high_thresh = 524288
      net.ipv4.ipfrag_low_thresh = 393216

echo 0 > /proc/sys/net/ipv4/tcp_sack
echo 0 > /proc/sys/net/ipv4/tcp_timestamps

TCP Segmentation offload

This will take off some of the tcp overhead if your card supports it..

# ethtool -K ethN tso on

Client Side

/etc/fstab

NFSv4 Client:

192.168.15.20:/mnt/raid5 /mnt/raid5 nfs defaults 0 0

NFSv3 Client:

192.168.15.20:/mnt/raid5 /mnt/raid5 nfs rsize=32768,wsize=32768,intr,hard 0 0

[rw]size=32768 - NFSv3 maximum read write size
intr - if the mount drops, you'll still be able to ^C out of whatever operation your running
hard - flush file locks before being able to unmount