performance issue on V2500 with Informix 7.31.FC6X7 and SAP 4.6b

[Varghese Mathew]

Hi Everyone,

We have an HP 9000 V2500 server and have recently upgraded the Informix to version 7.31.FC6X7 and the Application SAP to version 4.6B . After the upgrade we have noticed drastic performance degradation in the server. Most of the time CPU "0" is overloaded compared to other CPU's. A total of 11 CPU's are installed in our system.

Is there any issues or say any known patches need to be applied to the System (HPUX 11.00) with this kind of setup. We have not installed any patches during the time SAP/Informix upgradation.

The situation is very very critical at the moment,as the users are complaining from all over the world. If any one can help us on this, would be of great help..

Thanx in advance..
Cheers !!!
Mathew

[Rainer von Bongartz]

what was your INFORMIX release before the update ?? and please post your $ONCONFIG file

[Tim D Fulford]

Hi

We really need more details! but from the symptoms I know of two possible problems

1 -The problems I've seen on a V class relate to AIO. The box became CPU bound because we were using KAIO. The symptoms were that excessive system:User CPU utilisation was seen.

There were a couple of ways 'round this
1 Reduce the number of CPU VPs
2 Convert to Informix AIO VPs

We chose 2.

The cause was (v roughly) that when an KAIO request was woken up it polled ALL the CPU VPs. There is a point at which Load, & Num CPU VPs causes the CPU utilisation to shoot off the scale (well 100%) and a large proportion of this was due to system calls.

HP say (or said) this should be fixed in HPUX 11.i

2 - The primary oninit freezes, speak to Informix. You can see this as the primary oninit just racks up processes.

onstat -g ath | grep 1cpu
also forcing a checkpoint fails to return
onmode -c

I doubt this is the case as the version on Informix you are running on is much latter that the one's I know of.

As one last thing, you seem to be using the 64 bit version of informix, was your previous version the 32 bit version? If so, there is another avenue of investigation.

Good luck

Tim

[Varghese Mathew]

Hi Guys,

I was away from work for a long time, i am back at the moment, and i am replying to your queries.

Rainer, attached is the onconfig details.

Tim, yes we were using 32 bit version Informix earlier.

Thanx for ur patience and responses in advance
Cheers !!!
Mathew