topic Re: memory / swap problem? in Operating System - HP-UX

memory / swap problem?

matteo_4 — Thu, 30 Jun 2005 07:21:10 GMT

Hi all,
i have a b180l hp10.20ux with 128 mbram and 1.8Gbyte of swap area.
This workstation is connected to hp3070 test system.
When i run a process for test a device then appear this message:

Status: Running...out of memory on call to Calloc
Use your debugger to see a stack backtrace

what does it mean?

Thank you for your suggest.

Matteo

Re: memory / swap problem?

Stanimir — Thu, 30 Jun 2005 07:25:30 GMT

Check your kernel params:

maxdsiz
maxssiz,

If need, increase it /reboot needed /.

Re: memory / swap problem?

matteo_4 — Thu, 30 Jun 2005 07:52:34 GMT

maxdsiz > 536870912
maxssiz > 16777216

Sorry but i'm not so expert
are this values correct i've to increase it
and if i've to increase it how can do it?

Thank you very much.

Re: memory / swap problem?

A. Clay Stephenson — Thu, 30 Jun 2005 09:23:16 GMT

Calloc sets errno to ENOMEM for 3 possible reasons 1) maxdsiz limit 2) out of swap 3) ulimit -d.

Do a ulimit -d; does it match your maxdsiz? If it's less then you have hit ulimit.

You could increase maxdsiz to 1GB but on your system this is a bit ridiculous because eventhough HP-UX is a virtual memory system with only 128MB of memory; in practical terms, your maxdsiz is already as big as it should be --- and performance is terrible.

Re: memory / swap problem?

matteo_4 — Fri, 01 Jul 2005 06:14:35 GMT

hi clay,
i've done the ulimit -d and the repor t is 524288.
My maxdisiz is i think that match beacause is 536870912.

So now you think if i expand my maxdsiz at 1gb i can't resolve my problem?

Yes the workstation have 128Mbram.

thank you very much.
regards
matteo

Re: memory / swap problem?

A. Clay Stephenson — Fri, 01 Jul 2005 09:26:21 GMT

No, your ulimit -d and maxdsiz values are the same. Ulimit -d reports in 1KB blocks so you do the math. Both are set to 512MB.

Note that you have over 14X as much swap as physical memory. This is really a ridiculously large amount of swap because if you ever need to use that much, your machine will be thrashing itself to death and performing very little useful work. You could increase maxdsiz up to 1GB but your current value is already dangerously high given your limited amount of physical memory.

Re: memory / swap problem?

Bill Hassell — Fri, 01 Jul 2005 15:28:48 GMT

Since the 3070 is a pre-built application system, your local login may have ulimit -d set OK but the program giving you the error may not have the same environment. As Clay said, maxdsiz and ulimit -d are at 512 megs, but if your program needs 800 megs, then you need to bump up the maxdsiz value so the prgram will actually run, albeit very slowly. Yes, you can run 800 megs of programs in 128megs of RAM as long as you have lots and lots of time to wait around for it to run. The B180 is so old that finding RAM (or even a complete system) for a few dollars is well worth the effort. You can verify this with vmstat and swapinfo -tm. If you see the po column in vmstat is 2 digits or more (when the system is very busy) or that your swap area is actually being used, adding 1Gb of RAM will tremendously improve the B180's performance.

Re: memory / swap problem?

matteo_4 — Wed, 06 Jul 2005 06:42:43 GMT

ok thank you very much i think i'm going to buy new 1Gb di ram.
Regards
Matteo