topic Re: memory usage in Operating System - HP-UX

memory usage

Vijaya Kumar_3 — Wed, 15 Oct 2003 09:55:23 GMT

Hi
I have a rp7410 (HP-UX 11.11 U)running with two oracle instances. it has 4 cpus & 8 gb of memory and two oracle instances are running.
I have performance problem and getting 100% memory usage
this is the memory usage (glance):

Total VM : 6.16gb Sys Mem : 1.44gb User Mem: 3.66gb Phys Mem: 7.99gb
Active VM: 3.41gb Buf Cache: 2.83gb Free Mem: 60.6mb

someone tell me why it shows user memory as 3.66 gb ?

i am also in the process of tuning some kernel parameters.

I have March 2003 Support Tools Patch bundle installed. if anyone recommend some strategy u follow that will a great help to me

any ideas?

Thanks in advance
Vijay

Re: memory usage

Pete Randall — Wed, 15 Oct 2003 09:57:32 GMT

Viajy,

Check your dbc_min and dbc_max parameters. Buffer cache should be no more than about 400 MB.

Pete

Re: memory usage

Jeff Schussele — Wed, 15 Oct 2003 09:59:06 GMT

Hi Vijay,

First thing that stands out to me is Buffer Cache size. You should really back that off so that it only uses 300-400MB of memory. Either do that through smaller dbc_max_pct or a hard set NBUF value. That will give you 2GB back immediately

Rgds,
Jeff

Re: memory usage

Michael Steele_2 — Wed, 15 Oct 2003 09:59:30 GMT

I can tell better with 'sar' myself, and there can be patching issues and bugs in gpm:

sar -u 5 5
sar -d 5 5
sar -v 5 5
sar -b 5 5
vmstat 5 5
swapinfo -tam
kmtune -q dbc_max_pct
kmtune -q dbc_min_pct

Thanks!

Re: memory usage

Vijaya Kumar_3 — Wed, 15 Oct 2003 10:04:09 GMT

I have these values
dbc_max_pct 50
dbc_min_pct 5

What about setting these values
dbc_max_pct 5
dbc_min_pct 3

Thanks
Vijay

Re: memory usage

Jeff Schussele — Wed, 15 Oct 2003 10:06:51 GMT

Hi (again) Vijay,

Yep - that's a good value.
Remember these changes require a reboot.

Rgds,
Jeff

Re: memory usage

Vijaya Kumar_3 — Wed, 15 Oct 2003 10:20:15 GMT

I was reading a Tunable Kernel Parameters Book and i have seen this parameters. I forgot to look into it.

Thanks Pete, Jeff and Michael.

I appreciate your help.

-Vijay