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

memory question

Ragni Singh — Fri, 19 Apr 2002 14:55:34 GMT

Hey guys,

how does one prevent itself from runnng out of memory?

How can I control the amount of memory a process can use?

Re: memory question

Hai Nguyen_1 — Fri, 19 Apr 2002 15:07:29 GMT

Sanman,

If you have glance, you can configure it in advisor mode to notify you of memory botteneck.

In addition, you can take a look at HP optional product which allows you to specify a specific amount of system resource for a specific process (or a group of processes.)

Hai

Re: memory question

Hai Nguyen_1 — Fri, 19 Apr 2002 15:10:01 GMT

Sanman,

I forgot to mention the HP optional product which is Process Resource Management (PRM.)

Hai

Re: memory question

MANOJ SRIVASTAVA — Fri, 19 Apr 2002 15:13:13 GMT

Hi Sanman

The first and foremost thing is to know what can the system handle . Please check for the kernel parameters to know the limits of the system and tune them in case you think that there something lacking .

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

is a popular place to look for the limits , also you need to look for o/p's of glance , vmstat to know whether you are saturating the memory or not.

Manoj Srivastava

Re: memory question

A. Clay Stephenson — Fri, 19 Apr 2002 15:17:03 GMT

Those values are ultimately controlled by the maximum addressable space. There are three kenel values maxtsiz (text or instructions), maxdsiz (initiazlized data, dynamic memory), and maxssiz (stack space, local unitialized variables). There are also 64bit versions of these vales. These three tunables define the maximum values on a global basis. It is normally a good idea to not set these values to extremely large values because this can allow a rogue process to grab all the system resources. You can also use the ulimit command to decrease these settings for a particular process but only a super-user is allowed to increase them.