HP-UX Error 12

[N.SivaramaKrishnan]

Hello,
I'm using Hp-UX B2000 with 9GB hardlisk. I've installed Oracle 8.1.7. The problem is that when I'm trying to bring up oracle using startup from svrmgrl prompt I'm getting the following error.

SVRMGR>startup
ORA-27102: out of memory
HP-UX Error: 12: Not enough space

Would be great if any one could give me the reason for this. Here are my kernel parameter values:
maxdsize - 3147483648
shmmax - 1073741824
swapmem_on - 1

I'm badly in need of this machine and would appreciate quick help from somebody.

Thanks in Advance
Regards
Siva

[Joseph Loo]

Have you also change this?

shmmax=1073741824 or 0X40000000
shmmni=100
shmseg=10
semmns=1000
semmni=100

NOTE: If you are installing the 64-bit version of Oracle, you must also increase the kernel parameter MAXDSIZ to 384M or higher in order to prevent an 'out of process memory' error during relinking.

If you have Metalink, you may want to check Doc ID: Note:108387.1.

Regards,
Joseph.

[Carlos Fernandez Riera · Accepted solution]

Do an aproximation of total SGA size:

edit init$ORACLE_SID.ora

Multiply:
db_block_size = 8192 by
db_block_buffers = 5000
and add
shared_pool_size = 40485760

8192*5000=40960000+40485760=81445760.

You SGA will be greater than 81445760.

shmmax must be greater that this value.

[N.SivaramaKrishnan]

Hi there,
My db_block_size is 8192, db_block_buffers is 2048 and shared_pool_size is 157286400 and the final value is lesser than the value of shmmax. Anyway thanks for the information.

Regards
Siva

[N.SivaramaKrishnan]

Hi there,
Do you want me to change shmmax or verify the value? The values of shmmni, shmseg, semmns and semmni were 200, 120, 250 and 256 respectively. I changed the value of semmns to 1000 and then rebuilt the kernel, but I got the same error ( no enough memory). Anyway thanks for the information.

Regards
Siva

[Carlos Fernandez Riera]

174.063.616 Bytes.


Now run swapinfo -a and see reserved size, and swap utilization.

Is swap space size configured with at least physical memory size?

[Andreas D. Skjervold]

Hi

Check your swapspace and that you infact have enough free memory.

Try reducing the SGA size to a minimum.

Andreas

[N.SivaramaKrishnan]

When I gave swapinfo I got the following info:
TYPE Kb Kb Kb PCT
Avail Used used Used
dev 1048576 0 1048576 0%
reserve - 202944 -202944
memory 381668 35840 345828

I'm not sure what I should I proceed with. Plse do give me some other additional information.

Thanks & Regards
Siva

[Bill Hassell]

This is likely only a 32bit version of Oracle and as such, you are constrained to a very small SGA....maxdsiz is only a fence but will not enable Oracle to address more RAM than is allowed in 32bits.

SGA (in 32 bit shared memory) is mapped into a single addressing space where it is shared with memory mapped files, other shared memory segments and shared libraries. It is likely that there is no single segment free that is large enough for the SGA you are requesting. Try reducing your SGA to just a few hundred megs and run it again.

To see the fragmentation in your 32bit memory area, get a copy of shminfo:

ftp://contrib:9unsupp8@hprc.external.hp.com/sysadmin/programs/shminfo/

64bit programs do not have this limitation of a shared memory area. You may also want to look at memory windows to give Oracle a clean address space. Note that if your overall RAM is small (less than 4000 megs), paging (swapping) will severely impact the performance of Oracle in a busy environment. Be sure to read the 3 white papers in /usr/share/doc on mem_mt, proc_mgt and memory windows (may require patches to add memory windows to your version of HP-UX),

[Magdi KAMAL]

Hi,

You wrote that the maxdsize is :

maxdsize - 3147483648 ???

Three Gigs for the max data size !!!

Are you sure you still have memory for the others :

. hp-ux
. Applications
. Tools
. Interactive users


How much physical memory and swap you have ???

Magdi

[T G Manikandan]

Hello,
your problem is definitely your Oracle database SGA exceeding your shared memory on the system.Please reduce your SGA to resolve your problem.
If your Oracle application is 32 bit then your memory on the server can be used only to a extent.
Just go thru' this link.
http://forums.itrc.hp.com/cm/QuestionAnswer/1,,0x5694c3d7fb78d4118fef0090279cd0f9,00.html


To resolve the error please reduce your SGA size and start the database.
If you have a big value for the large_pool_size or shared_pool_size just reduce that and try starting your database.
Then the problem can be investigated in detail

Thanks
G Manikandan

[N.SivaramaKrishnan]

I reduced the shared_pool_size and then tried and even then I'm getting the same error. The reduced value is 15728640 and the old value being 1572864000. I need atleast 15Megs as the shared memory.
An workaround is made by adding one more swap space and the problem of memory is not occuring.

Siva

[Admin.SIF]

Hi

[pap]

Hi,
You have to set "maxdsiz" parameter to a value equal to 2 GB. (0x7B03A0000) for 32 bit operation.

You may have to increase your swap memory depending upon the physical memory size.

[pap]

Hi,
Are you still getting error?
Your problem solved????

Please update us so that we can have idea what is going on at your end.

Thanks,

[N.SivaramaKrishnan]

Hi there,
Still the problem is occuring. As I said the workaround which I handled is that, I added one more swap space (paging) and it worked fine. But the size is getting increased drastically and I don't have so much of hard disk space to hold that. If any of you can give me any suggestions that would be great.

The value of maxdsiz is around 3GB.

Siva

[Andreas D. Skjervold]

Hi

To reduce the need for swapspace you can use the function called "psuedo-swap".

This is set up in the kernel and kindof fools the applications to belive there is swapspace available when there is not.

This us useful when running applications that must recide in physical memory (such as Oracle SGA) as you then never will utilize the swapspace.

How to set it up?
Set the kernel parameter "swapmem_on" to 1

Andreas

[N.SivaramaKrishnan]

All,
I was changing the wrong init$SID.ora file and when I changed the exact file, I was able to bring up the oracle. But even then I need more shared memory for oracle (that can be set using shared_pool_size) and if I increase that I'm not able to bring up the database. So I need some workaround to make it work (one would be to add one more hard disk, but that's costlier). I appreciate all your help for fixing this.

Thanks & Regards
Siva

[pap]

Hi Shiva,

HAve you solved your problem? or still trying.
Please kindly update if you already resolved it. Also provide correct the resolution so that we can keep that in our mind.


Also, It will be great if you can assign points to all.

[N.SivaramaKrishnan]

Hi there,
It is because of the very large value that is used for shared_pool_size. I reduced that to a reasonable value and I no longer face that problem. Thanks for everybody effort in helping me.

Pap,
Sure. I'll assign points to everybody based on the answers.

Thanks & Regards
Siva