The file transfer size establishes the size of the buffers that are used when data is transferred between the client and the server. In general, larger transfer sizes are better. The NFS Version 3 protocol has an unlimited transfer size. Although the client can bid a smaller transfer size at mount time, under most conditions, this bid is not necessary.
The transfer size is not negotiated with systems that use the NFS Version 2 protocol. The maximum transfer size is set to 8 Kbytes.
You can use the –rsize and –wsize options to manually set the transfer size with the mount command. You might need to reduce the transfer size for some system clients. Also, you can increase the transfer size if the NFS server is configured to use larger transfer sizes.