topic Re: nfiles in Operating System - HP-UX

nfiles

Art Mehlman — Tue, 28 Sep 2004 08:05:02 GMT

Please assume I am an experienced admin who can read and google.
I have read about nfiles, but not sure of what I have read.
I am running hp-ux 11.11 with oracle 9.2.
SD Npar with 4 cpus and 16GB mem
Potentially 2500 users.
we see about 16-1700 hundred users on avg.
Currently nfiles is set to 85000 and we are seeing it hit the max open files.
I would like to increase it to 100k, but would like to under stand the impact on the system before I do this.

TIA

Re: nfiles

Pete Randall — Tue, 28 Sep 2004 08:17:30 GMT

Art,

The only real impact is a small increase in the size of the kernel. Quoting from SAM's help on kernel configurable paramaters:

"nfile defines the maximum number files that can be open at any one time, system-wide.

It is the number of slots in the file descriptor table. Be generous with this number because the required memory is minimal, and not having enough slots restricts system processing capacity. "

Pete

Re: nfiles

Prashant Zanwar_4 — Tue, 28 Sep 2004 08:28:18 GMT

Hi,

You have to be really sure about the impact on the system. Some good document will help you in deciding what you can go for. And also you can compare on the systems in your setup.
Bump nfile up if you see high File Table utilization (>80 percent) in
Glance (System Tables Report) or get "File table overflow" program errors. Use a similar
approach for nflocks (max file locks). If you are configuring a big filesystem server
then you're more likely to want to bump up these limits.

Hope above helps

THanks
Prashant

Re: nfiles

Franky_1 — Tue, 28 Sep 2004 08:28:44 GMT

Hi Art,

"nfile defines the maximum number files that can be open at any one time, system-wide."

The required memory is minmal an the maximum numer is only memory limited

You shouldn't worry to much about your increase to 100k

Regards

Franky

Re: nfiles

Muthukumar_5 — Tue, 28 Sep 2004 08:52:47 GMT

When you are trying to analyse nfiles kernel parameter then try to check associated parameters too.

maxfiles
maxfiles_lim
nproc

You can get the associativeness with kmtune as,

kmtune -n -q

Refer this for more.
http://www.atg.com/repositories/ContentCatalogRepository_en/manuals/ATG6.2.0/installdas/installdas1923.html

Re: nfiles

Muthukumar_5 — Tue, 28 Sep 2004 08:54:56 GMT

Try kmtune as,

kmtune -l -q

Re: nfiles

Art Mehlman — Tue, 28 Sep 2004 10:03:06 GMT

Thanks for the insights.