The Performance of a Linux NFS Implementation

NFS is the dominant network file system used to share files between UNIX-derived operating system based hosts. At the onset of this research it was found that the tested NFS implementations did not achieve data writing throughput across a Gigabit Ethernet LAN commensurate with throughput achieved with the same hosts and network for packet streams generated without NFS. A series of tests were conducted involving variation of many system parameters directed towards identification of the bottleneck responsible for the large throughput ratio between non-NFS and NFS data transfers for high speed networks. Ultimately it was found that processor, disk, and network performance are not the source of low NFS throughput but rather it is caused by an avoidable NFS behavior, the effects of which worsen with increasing network latency