kmtune and parameter not stored into kernel

[Sebastien Masson]

Hi all.

This morning I found that kmtune display some kernel parameter with no current value ('-'). The man said:

The Current field is an integer read from the running kernel. Some parameters are not stored in the running kernel and are displayed as '-'.

And those parameter doesn't appear in SAM ?!

What that mean ? Does the kernel use them ? does it required only for specific hardware which I don't have ?

Some example:

iomemesize
minfree
netisr_priority
netmemmax

Thanks

[Massimo Bianchi]

Hi,
I know abot minfree, it is hardcoded in the kernel.

You can view its value with:

# echo minfree/D | adb /stand/vmunix /dev/kmem

It is used for determining the desidered minumun number of free memory pages in the system.

I think the same (for viewing)could be done for the other parameters.
But i would not play with them too much...

HTH,
Massimo

[Michael Steele_2]

Self tuning parameters are becomming more common as newer version of HP-UX are released. There are others that are undocumented for a variety of reasons. Some are obsolete, some are associated with independent software subsystems, some can result in severe system malfunctions if they are altered without proper understanding, and some are not supported by SAM.

Here is a list of configurable kernel parameters:

http://docs.hp.com/hpux/onlinedocs/939/KCParms/KCparams.OverviewAll.html