Managing NFS and KRPC Kernel Configurations in HP-UX 11i v3 (762807-002, June 2014)

2.1.42 nfs4_pathconf_disable_cache
Description
The nfs4_pathconf_disable_cache tunable controls the caching of pathconf(2) information for NFSv4
mounted filesystems.
The nfs3_pathconf_disable_cache tunable controls the caching of pathconf(2) information for NFSv3
mounted filesystems. For more information on the tunable, see nfs3_pathconf_disable_cache.
Tested Values
Default: 0 (Pathconf cache is enabled)
Min: 0
Max: 1 (Pathconf cache is disabled)
Restrictions on Changing
The nfs4_pathconf_disable_cache 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 the
nfs4_pathconf_disable_cache tunable.
Modifying the Value
If you have an application that is making pathconf calls and needs real-time information from the
backend filesystem, turn off pathconf caching by setting the value of the tunable to 1.
2.1.43 nfs_enable_ufc_threshold
Description
The nfs_enable_ufc_threshold tunable controls the NFS client’s usage of UFC file cache.
If the user sets the filecache_max parameter to a very low value, say 1%, then based on work load,
the NFS client could consume all the UFC file cache. In such scenarios, users can enable this tunable
to force the NFS client to use only limited percentage of UFC filecache which is controlled by another
tunable nfs_ufc_threshold_percentage
For more information on the tunable, see nfs_ufc_threshold_percentage
Tested Values
Default: 0 (nfs_enable_ufc_threshold is disabled)
Min: 0
Max: 1 (nfs_enable_ufc_threshold is enabled)
Note: This tunable is implemented only for NFS v3 mounts
and v4 mounts.
Restrictions on Changing
The nfs_enable_ufc_threshold tunable is static. All NFS mount points must be unmounted before
enabling or disabling this tunable. The nfs_enable_write_behind tunable must be enabled before
enabling this tunable. In case the filecache_max parameter needs to be modified, users must enable
this tunable again even if it is enabled already. This allows the NFS client to recalculate the internal