Deadlock problem? Me too!

jtwigge_at_attistel.co.uk (Jon Twigge) wrote:
> We are having problems on an SMP box with multiple parallel threads of
> execution causing apparently random deadlock messages. This is
> happening across a number of different jobs and we are increasingly
> convinced that they are not genuine data-related deadlocks.
> Single-streaming fixes the problem.

I have observed what could be related problems. I am running Oracle 7.2.2 under HP/UX 10.01 on an HP 9000/K200 with dual processors. I have observed problems with certain large transactions. We have some transactions that insert several thousand records, spread across roughly 300 tables. I recently ran an experiment where I performed an Oracle startup and then processed several of these transactions without any other Oracle sessions running. Periodically, the Pro*C program processing the transactions would go idle for several minutes.

While monitoring the locks and processes through the Server Manager, I observed the process was waiting for a requested lock during this idle period. Eventually processing would resume and processing would run to normal completion. This problem has never been observed on our single processor HP/UX systems. Does anyone have any suggestions for resolving this problem? Thanks!

• Andy Zitelli