hpux man page for ncsize

ncsize(5)							File Formats Manual							 ncsize(5)

NAME
       ncsize - number of Directory Name Lookup Cache (DNLC) entries

VALUES
   Failsafe
   Default
   Allowed values
       The  minimum value allowed is The maximum value allowed is memory limited.  The value is further constrained in that it must be equal to or
       greater than eight times the value of the number of locks for the DNLC

       Specify a positive integer value.

DESCRIPTION
       To speed up the search through directories in the kernel, there is a memory resident cache of directories  called  the  During  a  filename
       lookup  in the kernel, any directories or files encountered are retained in the DNLC for future reference.  The tunable dictates the number
       of entries in the DNLC, which is statically allocated at system boot time.  Therefore, the larger the value of the  larger  the	number	of
       directory/file entries that can be kept cached in memory for filename lookup.

   Who Is Expected to Change This Tunable?
       HP-UX system administrators.

   Restrictions on Changing
       This tunable is static.	Any changes to the value of this tunable will require system reboot before taking effect.

   When Should the Value of This Tunable Be Raised?
       The  value  may	need to be raised to improve filename lookup performance when running applications which require large numbers of filename
       access.

   What are the Side Effects of Raising the Value?
       More system memory will be consumed for the DNLC.

   When Should the Value of This Tunable Be Lowered?
       The value can be lowered to limit the number of entries in the DNLC and reduce memory consumption.

   What are the Side Effects of Lowering the Value?
       Less system memory will be consumed for the DNLC upon system reboot.  Operations requiring filename lookup (e.g.  open(2))  may	experience
       performance degradation.

   What Other Tunable Values Should Be Changed at the Same Time?
       The value of must be equal to or greater than eight times the value of

WARNINGS
       All  HP-UX kernel tunable parameters are release specific.  This parameter may be removed or have its meaning changed in future releases of
       HP-UX.

       Installation of optional kernel software, from HP or other vendors, may cause changes to tunable  parameter  values.   After  installation,
       some  tunable  parameters may no longer be at the default or recommended values.  For information about the effects of installation on tun-
       able values, consult the documentation for the kernel software being installed.	For information about optional kernel  software  that  was
       factory installed on your system, see at

AUTHOR
       was developed by HP.

SEE ALSO
       kctune(1M), sam(1M), gettune(2), settune(2), dnlc_hash_locks(5).

							     Tunable Kernel Parameters							 ncsize(5)