HELP! VMS Ada process in MUTEX state

Hi,

my program is slow on an otherwise empty VAX. It runs as a detached process. It is given some quota which seem appropriate, but I'm no expert on this. My sysman ran sysgen during a session, and he found nothing alarming. But still my process is slow. put_line's displaying times indicate:
- that task switching may be involved.

• it's not Oracle queries that take long. Page faulting is low. There's enough core memory.

Characteristics of the process:
It's linked with Oracle7 (directly, not 2-task), using PRO*Ada. Because of Oracle, timeslicing is disabled. About 10 tasks, most of them idly waiting for a mailbox read. The process reads commands from mailboxes, executes them, and puts results back on other mailboxes.

Many moderately experienced people have gathered around me, monitor-ed, sho sys-ed, sqldba-ed, but nobody can find what's going on. The process is nearly always in the MUTEX state (as shown by SHOW SYSTEM), a.k.a. the MWAIT state (as show by SHO PROC/CONT). It does what it is supposed to do, but 1 minute for deleting 4 Oracle rows and some housekeeping seems a little slow.

I understand that MUTEX is something like waiting for a semaphore to be freed. But I don't understand what this semaphore protects. Is it disk space, core memory, Oracle shared memory, something in the Ada RTL?

My questions are:

Does anybody have a clue what's going on?

Where should I look for now?

I'd be very happy to provide you with additional information, if that's necessary.

Thanks for your attention!

-- 
Gijs Bok (gijs_at_mbase97.hacktic.nl)
Listen to M-BASE music!
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