Out of Memory error

[Shivkumar]

Hi,

We sometime see "Out of Memory" error on WebLogic Server 7.0 running on HPUX 11i.

Appreciate if someone can share any inputs.

Thanks,
Shiv

[James R. Ferguson]

Hi Shiv:

This can arise from insufficient swap space (for a process's swap reservation) or from insufficient (usually) data stack space ('maxdsiz' or 'maxdsiz_64' for 32-bit and 64-bit processes respectively).

I'd examine swap utilization with:

# swapinfo -tam

I'd use 'kmtune -l' to ascertain the kernel paramter settings mentioned.

Regards!

...JRF...

[Kent Ostby]

Shiv --

Keep in mind that HP recommends 2xRAM worth of device swap.

So if you are running 4 GB of RAM, you should have 8 GB of DEVICE SWAP (not including swapmem).

Oz

[Bill Hassell · Accepted solution]

Most conditions for Out of Memory are really not due to lack of RAM or virtual memory (swap space). The error is often related to 'safety' parameters that limit the maximum size of a program's data area. But before you can do anything, you must determine the program that is complaining and see if it is a 32bit program.

If so, there are many restrictions on the size of the program and how it was compiled. Start with the kernel parameter maxdsiz which governs the maximum data area for a 32bit program. Unless changed, it is either a paltry 64megs or (still small) 512megs. Use SAM to change maxdsiz to about 1800megs. Also make sure that maxdsiz_64 is larger than maxdsiz, perhaps 2x larger.

Now if the WebLogic program is a 32bit program but was not compiled to as an EXEC_MAGIC program, it cannot grow larger than 960megs in the data area. WebLogic support should be able to help with compiler options (if available).

[Shivkumar]

We noticed this "out of memory" error in WebLogic log file. We run WebLogic 7.x on HPUX 11i.

[Arunvijai_4]

Hi Shiv,

What is your physical and virtual memory size ?

You can use # /opt/ignite/bin/print_manifest to find out.

Also, have you applied latest patches for Java on HP-UX and Weblogic 7.0 ?

-Arun

[RAC_1]

Post following.
swapinfo -mat
kernel settings for
maxdsiz and maxdsiz_64bit
maxtsiz and maxtsiz_64bit
maxssiz and maxssiz_64bit