Kernel Changes

[David Dangerfield_1]

I need to make the following changes and wanting to see what affects could happen.

1. NCSIZE from 4624 to 43072
2. NFILE from 10240 to 77048
3. NINODE from 3600 to 42048
4. VPS_CEILING from 16 to 64

The VX_NCSIZE currently is 1024 which will stay the same for the NCSIZE.

This is all being done because of an Oracle Database

[James R. Ferguson · Accepted solution]

Hi David:

The Tunable Kernel Parameters guide does a good job of explaining the use and the ramifications of changing the various tunables:

http://docs.hp.com/en/TKP-90202/index.html

Regards!

...JRF...

[Raj D.]

Hi David ,

Here is a good doc to check and understand of all tunable parameters,

Ex: VPS_CEILING

Variable Page Sizes :

The size of virtual memory pages can be altered to make swap operation more efficient in particular applications. Parameters include : vps_ceiling , vps_chatr_ceiling , and vps_pagesize .

[ Tunable Kernel Parameters.pdf ]
http://docs.hp.com/en/TKP-90203/TKP-90203.pdf

Cheers,
Raj.

[A. Clay Stephenson]

There is no point in increasing ncsize because it is an obsolete parameter. It is retained because some software might examine this value and require it to be at least a given size but that's really the only reason to increase - to "trick" some application software.

ninode at 3600 is already more than big enough. Ninode only applies to hfs filesystems and I'll bet the only hfs filesystem on your box is /stand. In that case, ninode at 1200 is more than generous. Your setting will do nothing except waste memory.

[David Dangerfield_1]

Problem was resolved without changing anything.