nfs:nfs3_dynamic

Description

Controls whether a feature known as dynamic retransmission is enabled for NFS version 3 mounted file systems using connectionless transports such as UDP. This feature attempts to reduce retransmissions by monitoring server response times and then adjusting RPC timeouts and read and write transfer sizes.

Data Type

Integer (32–bit)

Default

0 (disabled)

Range

0 (disabled), 1 (enabled)

Units

Boolean values

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

When to Change

In a situation where server response or network load varies rapidly, the dynamic retransmission support might incorrectly increase RPC timeouts or reduce read and write transfer sizes unnecessarily. Disabling this functionality might result in increased throughput, but possibly, also increasing the visibility of the spikes due to server response or network load.

Stability Level

Evolving