Managing NFS and KRPC Kernel Configurations in HP-UX 11i v3 (762807-001, March 2014)

administrator must unmount and re-mount the NFS filesystem
to use the new value.
Note: The nfs4_max_transfer_size_cots tunable affects every
NFSv4 filesystem. To control the transfer sizes of specific
NFS filesystems, use the rsize and wsize mount options.
Refer to the mount_nfs(1M) man page for more information.
2.1.41 nfs4_nra
Description
The nfs4_nra tunable controls the number of read-ahead operations queued by NFSv4 clients when
sequential access to a file is discovered. Read-ahead operations increase concurrency and read
throughput.
The nfs2_nra tunable controls the number of read-ahead operations queued by NFSv2 clients. The
nfs3_nra tunable controls the number of read-ahead operations queued by NFSv3 clients. For more
information on these tunables, see:
• nfs2_nra
• nfs3_nra
Tested Values
Default: 4
Min: 0
Max: 16
Note: If the tunable is set to a value greater than 16, an
informational warning is issued at runtime. Any value
greater than 16 is outside the tested limits.
Restrictions on Changing
The nfs4_nra tunable is dynamic. System reboot is not required to activate changes made to this
tunable. Only NFSv4 mount points are affected by changing the value of this tunable.
Modifying the Value
If the network has high available bandwidth and the client and server have sufficient CPU and
memory resources, increase the value of this tunable. This increase enables you to effectively utilize
the available network bandwidth as well as the client and server resources.
If the network has low available bandwidth, decrease the value of this tunable. This decrease ensures
that the NFS client does not overload the network.