nfs:nfs4_max_transfer_size Parameter

Description

Controls the maximum size of the data portion of an NFS version 4 READ, WRITE, READDIR, or READDIRPLUS request. This parameter controls both the maximum size of the request that the NFS server returns as well as the maximum size of the request that the NFS client generates.

Data Type

Unsigned integer (32-bit)

Default

32, 768 (32 KB)

Range

0 to 2³² - 1

Units

Bytes

Dynamic?

Yes, but this parameter is set per file system at mount time. To affect a particular file system, unmount and mount the file system after changing this parameter.

Validation

None. However, setting the maximum transfer size on the NFS server to 0 is likely to causeFS clients to malfunction or just decide not to attempt to talk to the server.

There is also a limit on the maximum transfer size when using NFS over the UDP transport. For more information about the maximum for UDP, see nfs:nfs3_max_transfer_size Parameter.

When to Change

To tune the size of data transmitted over the network. In general, the nfs:nfs4_bsize Parameter parameter should also be updated to reflect changes in this parameter.

For example, when you attempt to increase the transfer size beyond 32 KB, update nfs:nfs4_bsize to reflect the increased value. Otherwise, no change in the over-the-wire request size is observed.

If you want to use a smaller transfer size than the default transfer size, use the mount command's ‐wsize ‐rsize option on a per-file system basis.

Commitment Level

Unstable