Reserving swap space

[ramesh_6]

When i give swapinfo command the column for reserve shows 0 bytes reserved. But it also tells that reserved swap space in use as 93 bytes. Hence the total rserved swap space in use as -93 bytes.

Actually we increased the SGA memory of Oracle and after that Oracle was not coming up. I suspected Swap and found the above abnormal information. Can anyone pls clarify?

[Santosh Nair_1]

The reserve line in swapinfo just shows the amount of swap space used for reserve. You should be looking at the total line (when using swapinfo -tam) to see the total amount of swap being used.

In any case, I don't believe this is your problem. You didn't mention the error that Oracle is returning, but if the only thing you did was increase SGA, then perhaps its exceeding the kernel parameter for shared memory (shmmax). More details on the error Oracle returns would be helpful in diagnosing the problem.

-Santosh

[Magdi KAMAL]

Hi Ramesh,

I don't think that Oracle didn't startup due to swap problem affected by SGA space increase ( as Santosh siad ) because swap problem will be mentionned with oracle startup and also with other running application. Anyway, your swap should be at least 2 times the amount of memory ( RAM ).

You may see if the Shared memory segment is big enough to hold you new SGA structure ( I would say that your problem is due to this kernel parameter shmmax ).

May you append the error message ! Thnx
Magdi

[John Bolene]

Also, make sure you have pseudo swap enabled.

Set swapmem_on to 1 in kernel parms and make a new kernel.