Kernel parameter unknown

[Marco Hernandez Padill]

I have one HP 9000 with HP-UX 11.0 and when I use SAM i get this error message:
"SAM internal error:
The error handler has gotten the error code 0 of type. NOTE with the associated strings:
ncsize
(NINODE+VX_NCSIZE)"

And SAM shows ncsize as unknown parameter.
May somebody explain me what's the problem??
Thank's

[Marco Hernandez Padill]

I also found that the unknown parameter is vx_ncsize. When I changed this variable by a value (1024) SAM doesn?t send error.
How can I check if this parameter exist in the kernel???
Thank's

[James R. Ferguson]

Hi:

Try:

# sysdef

See: man sysdef

If you changed the formula value when you selected the kernel parameter for change, did you mistype something?

...JRF...

[Marco Hernandez Padill]

I have checked the kernel parameters and I didn?t find vx_ncsize. Have changed this parameter in HP-UX 11.0 ?
Thank's

[James R. Ferguson · Accepted solution]

Hi.

PHKL_18334 added 'ncsize' as a kernel parameter for 10.20.

PHCO_19047 for 11.0 states, in part, "The tunable parameters fcp_large_config,
hdlpreg_hash_locks, km_disable, ncsize, vx_ninode, vx_noifree, and scsi_max_qdepth are new to SAM."

Therefore, I would make sure you have 11.0 patch PHCO_21187. This may be the root of your problem.

...JRF...

[rajsri]

Hi
TRY TO INSTALL THE FOLLOWING sam/oBAM PATCH TO RESOLVE THIS PROBLEM. PHCO_21187


RAJU.

[Stacey Rippetoe]

FYI, in case you haven't seen it, there is some good kernel information at
http://docs.hp.com/hpux/content/KCparams.OverviewAll.html

[federico_3]

vx_ncsize specifies the number of bytes to be reserved for the directory path-name cache used by the VxFS file system.


The VxFS file system uses a name cache to store directory pathname information related to recently accessed directories in the file system. Retrieving this information from a name cache allows the system to access directories and their contents without having to use direct disk accesses to find its way down a directory tree every time it needs to find a directory that is used frequently. Using a name cache in this way can save considerable overhead, especially in large applications such as databases where the system is repetitively accessing a particular directory or directory path.

vx_ncsize specifies the how much space, in bytes, is set aside for the VxFS file system manager to use for this purpose. The default value is sufficient for most typical HP-UX systems, but for larger systems or systems with applications that use VxFS disk I/O intensively, some performance enhancement may result from expanding the cache size. The efficiency gained, however, depends greatly on the variety of directory paths used by the application or applications, and what percentage of total process time is expended while interacting with the VxFS file system.



I hope this helps you!