Managing NFS and KRPC Kernel Configurations in HP-UX 11i v2 (Oct 2008)

Caution: If the NFS client is experiencing NFS READ failures

and the system is reporting "NFS read failed for server

<servername>: RPC: Can’t decode result" errors, this is an

indication that the nfs3_max_transfer_size,

nfs3_max_transfer_size_clts, or nfs3_max_transfer_size_cots

tunable value was changed while NFS filesystems were

mounted. You must unmount and re-mount the NFS

filesystem to use the new value.

Note: The nfs3_max_transfer_size_cots tunable affects every

NFSv3 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.

2.1.22 nfs3_new_acache

Description

The nfs3_new_acache tunable enables you to specify the search algorithm to be used while searching

for an entry in the access cache. There are two search algorithms available: linear and hashed. The

linear search algorithm is the default. The speed of the hashed search is controlled by the number of

hash buckets. Activating the nfs3_new_acache tunable enables you to use the hashed search

algorithm which may improve performance for NFS applications. The nfs3_hacc_size tunable enables

you to specify the number of hash buckets to be used by the NFSv3 access cache. For more

information on the tunable, see

nfs3_hacc_size.

Tested Values

Default: 0 (Linear search algorithm is used)

Min: 0

Max: 1 (Hashed search algorithm is used)

Restrictions on Changing

The nfs3_new_acache tunable is dynamic. System reboot is not required to activate a change made

to this tunable. Only NFSv3 mount points are affected when you change the value of this tunable.

Note: If there are no NFS mount points in the system, any

change made to the value of the tunable is effective

immediately. If there are NFS mount points in the system, a

system reboot is required for the change to be activated.

Modifying the Value

If a file or a number of files is used by a large number of users, each having a unique uid, enable this

tunable to reduce the time required to search for an entry in the access cache on NFSv3 filesystems.