ORACLE MEMORY ERROR

[Nobody's Hero]

I have an N class running 11.0 16 gb of memory.
The kernel is tuned fairly well. However, I am running 4 instances each set to SGA=150 meg. When trying to start a fifth instance, SGA=150, I got a insufficient memmory error. I had to back the SGA down to 50 for the fifth instance and it came up OK. Are there any kernel parms that I can increase to allow this fifth instance to run at 150 SGA?

[Shahul]

Hi

What about nfile, nproc, shmmax ..etc. Then U monitor ur swapinfo while running the fifth instance. U can use sar, top, glance + like utilities to figure out the problem.

Best of luck
Shahul

[Dave Chamberlin]

some questions - what version of Oracle are you running, and is it 32 or 64 bit? Also, what is the kernel paramter dbc_max_pct set to?

[harry d brown jr]

Robert,

post your kernel parameters and swapinfo

live free or die
harry

[Jeanine Kone]

Something seems a bit odd here - you have 16 Gig of memeory, and your 4 instances take up 150 Meg each - that's 600 Meg total. What else do you have running on your machine that is using the other 15+ gig of memory?

[Nobody's Hero]

running oracle 8.1.7
64 bit
dbc_max_pct = 30
dbc_man_min = 5

Can someone tell me how to attach a file so I can post my kernel and swap?

[Nobody's Hero]

OK I see how to attach...will be posting in a couple minutes....

[Shahul]

Hi

If U go to reply option, below the box U will get a "brows" buutton. Here U can attach

Shahul

[Nobody's Hero]

See Attachment

[Nobody's Hero]

Another clip

[harry d brown jr · Accepted solution]

30%? Wow, that's 4.8GB. I'd trim that right down to about 2% max and 1% min.

To attach a doc, if using a PC, requires you to get the file onto your PC first.

Otherwise you can probably just cut & paste into this window. It's just that attachments don't get reformated. Also, please make sure they are "TEXT" files and NOT WORD files (filename.doc).

live free or die
harry

[Nobody's Hero]

So that would be 20 and 10 for dbc, I'm guessing. You say 4.8 gb whent set to 30%? What are you saying, that the system is reserving 4.8gb of memory for system processes?

[Uday_S_Ankolekar]

Well,
30 % dbc_max is way too more.
I would change dbc_max to 5 and dbc_min to 4 or less and see the performance.

-USA..

[Dave Chamberlin]

You definately want to reduce dbc_max_pct to a reasonable value like 3% in your case. Also attach a copy of the initORA parameters - the SGA may not be the problem.

[MANOJ SRIVASTAVA]

Robert

What is the value of SHHMAX , you need to increase it to accomadate the new instance.

Manoj Srivastava


( press browse to attach a file )

[Nobody's Hero]

shmmax = 1,073,741,824

Does this seem too low???

[Jeanine Kone]

I'm sure someone else will answer thisin more technical terms than I can but:

The way I understand it is that shmmax is the max size of a single shared memory segment. It must be large enough to fit the whole SGA. But, you can have more than one segment allocated - so for an SGA of under 1G, that would be fine.

[harry d brown jr]

Robert,

Bump it up to 2GB, and reduce your dbc max and min (of which 5% would be a high max setting).

live free or die
harry

[Nobody's Hero]

Here is my initORA

[Nobody's Hero]

Thanks Harry, that seems to have helped. My 5th instance was slow but it started. What is your approximate salary with all your knowledge around 500K. Just kidding. Anyway, what would be the max setting in my circumstance, for shmmax?

Again, thanks to everyone....

Bob Menefee

[Jeanine Kone]

Just for the sake of furthering my (and anyone else who might read this for an answer sometime) knowledge and understanding, could someone please tell me if my understanding of the shmmax parameter was incorrect? If not, why would increasing it fix the problem?