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

2.1.3 nfs_do_purge_rddir_cache
Description
The nfs_do_purge_rddir_cache tunable controls how an NFS client manages the readdir cache
contents. If an NFS mounted filesystem has a huge directory hierarchy with a large number of files,
and this mounted directory is referenced, large numbers of directory cache entries are created. The
huge directory cache can build pressure on system memory. When this tunable is enabled, it frees the
directory cache. This eases the load on memory.
Tested Values
Default: 0 (Directory cache is not purged)
Min: 0
Max: 1 (Directory cache is purged)
Restrictions on Changing
The nfs_do_purge_rddir_cache tunable is dynamic. System reboot is not required to activate a change
made to this tunable. Changes made to the nfs_do_purge_rddir_cache tunable are applicable to all
NFS mounted filesystems.
Modifying the Value
Enabling the tunable helps NFS use memory more efficiently. However, enabling this tunable also
results in more over-the-wire requests from the client as the directory information is not cached. This
tunable is not available in the next release of HP-UX. Starting with the HP-UX 11i v3 release the NFS
client uses a different mechanism for recovering memory when the system is under memory pressure.
2.1.4 nfs_new_filelock_cancel
Description
The nfs_new_filelock_cancel tunable enables new logic for cancelling lock requests.
Tested Values
Default: 0
Min: 0
Max: 1
Restrictions on Changing
The nfs_new_filelock_cancel tunable is dynamic. System reboot is not required to activate a change
made to this tunable. Changes made to the nfs_new_filelock_cancel tunable are applicable to all NFS
mounted filesystems.
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.
Before you enable this tunable, you must install the following
patches:
PHNE_38252 NFS
PHNE_38253 Lock Manager
PHKL_38288 File descriptor management; voncelocked fix
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