I've had 2 database crashes in the last week with the same error being shown in the online.log :

15:43:17 dynamically allocated new shared memory segment (size 33554432)

15:53:59 shmget: [ENOMEM][12]: key 5257480c: out of shared memory, check system SHMALL

I'm running IDS 7.23 UC6 on HP-UX 11.0 (32-bit) - mahcine has got 3.75 GB memory. SHMTOTAL is set to zero and kernel parameter shmmax is 1GB (which is it's maximum value). Is it just a simple matter of the Vertual segment of the Online memory can't go above 1GB ?

Any ideas would be appreciated.

Richie

Run onstat -g seg and see the Total Shared memory size, if you happen to exceed 3.9Gb, the engine's daemon "oninit" disconnects from the Shared memory and you'll not be able to issue anymore onmode's to free the VM. At this point the only option is to kill the oninits and restart with the following.
Set your SHMADD 64000
Set Your SHMTOTAL 3.85Gb
If your system is tuned for DSS, check who is issuing monstrous queries without PDQ environment variable and ask them to set it, until then , you can scale down the DS_TOTAL_MEMORY to 50% of VM.

Hope this helps.
-Abraham

Thanks for this, Abraham.

Where is the limit set to 3.9GB ? It would appear on HP-UX 11.0 (32-bit), the limit is 1GB - set by kernel parameter "shmmax".

Is is just a matter of upgrading the version of HP-UX to 64-bit and the version of Online to version 9 ?

Any help, appeciated.

Richie

With the IDS 9.4 onwards, the unlimited shared memory has been implemented. Check with Tech support as to the release from which this is implemented, might be as early as IDS 9.3.

Going to IDS 9.4 with the 64Bit combination, you also get the "Large Chunks" capability.

-Abraham