topic Kernel tunning in Operating System - HP-UX

Kernel tunning

Jose Mosquera — Fri, 13 Jun 2003 14:49:48 GMT

Hi Pals,

In HP-UX 11.0 we are trying to load a file (60Mb) into a dynamic memory table, when the loading proccess have reached 25Mb the proccess go down with the following message error:
Fatal error: 9010 - Out of memory; cannot claim more; total segmented
memory claimed.

We suppose that this issue is involving a kernel tunning due to we have noticed that maxssiz and maxssiz_64bit looks lower to satisfy our requirements (Pls find attached a copy of our current kernel conf).

I'll appreciate your comments and recomendations about.

Regards.

Re: Kernel tunning

Bill McNAMARA_1 — Fri, 13 Jun 2003 14:56:22 GMT

http://docs.hp.com/hpux/onlinedocs/939/KCParms/KCparams.OverviewAll.html

Later,
Bill

Re: Kernel tunning

Jeff Schussele — Fri, 13 Jun 2003 14:57:01 GMT

Hi Jose Maria,

Your kernel parms look a little low, but high enough to allow this.
Is it possible that this is a 32-bit application? Limiter could be contigous memory.
You could not have enough in one chunk to load this.
Check your shared memory with

ipcs -mob

HTH,
Jeff

Re: Kernel tunning

Steven E. Protter — Fri, 13 Jun 2003 14:59:22 GMT

A great performance tuning doc.

Performance Tuning doc

http://www1.itrc.hp.com/service/cki/search.do?category=c0&docType=Security&docType=Patch&docType=EngineerNotes&docType=BugReports&docType=Hardware&docType=ReferenceMaterials&docType=ThirdParty&searchString=UPERFKBAN00000726&mode=id&admit=-682735245+1053636168960+28353475&searchCrit=allwords&printable=true

I know the author who deals with Oracle performance issues at the support center. He is the top of the field.

SEP

Re: Kernel tunning

Bill Douglass — Fri, 13 Jun 2003 15:03:52 GMT

I think it is maxdsize that is you problem, not maxssize.

It looks like your default maxdsize may be too low (64MB). You can use SAM to rebuild your kernel with a larger value and retry your app.

Also, what size chunks are you allocating memory in?

Re: Kernel tunning

Jose Mosquera — Fri, 13 Jun 2003 15:10:04 GMT

Hi,

I've read the Configurable Kernel Parameters white paper before this consult, thanks.

Development team have to certify me n-bit application, and our shared memory are in attached doc.

Rgds.

Re: Kernel tunning

Caesar_3 — Fri, 13 Jun 2003 15:15:17 GMT

Hello!

Try to work with SAM for rebuild the kernel
there you will have some info about every
parameter that you can change.
I think you should change the maxdsiz
the one that is write to your OS 32/64bit
check that you change the wright.

Caesar

Re: Kernel tunning

Jeff Schussele — Fri, 13 Jun 2003 15:31:19 GMT

Hi (again) Jose Maria,

Well seeing that shared memory output, I still believe that 32-bit shared memory exhaustion or fragmentation could be the culprit here.
You've got several processes in there that are large users.
Is this 11.0/32 or 11.0/64. If it's a K-class or lower it could be a 32-bit OS. If it's an L-class or higher it's definitely 64-bit. But even if the OS is 64-bit, the application could still be 32-bit & could be the culprit.
If so, then you'll need to run memory windows.
See /usr/share/doc/mem_wndws.txt for the whitepaper on how to implement & use memory windows.

HTH,
Jeff

Re: Kernel tunning

Jose Mosquera — Mon, 16 Jun 2003 13:20:03 GMT

Hi Jeff,

This is a L-Class machine under HP-UX 64, and the application is a 32-bit code. Also we have Sybase 11.03 and 12 engines running inside the box in 64-bit modes. Would the activation of this feature impact exclusively to those of 32-bit or both? Do risks exist on those of 64-bit?

Regards,