Users per MTS Ora 9

We are experiencing intermittent performance problems with our Oracle 9.2 database. Usually fine then extremely slow (unusable). We have done statspack, OEM. Running on AIX box. Monitoring (nmon64) shows the machine is falling asleep (cpu has never hit 80% and usually around 20%, paging fine, SCSI fine, disk nothing). Hit rates are > 99% with giant SGA. We seemed to do better on slower machine with Oracle 8.1.7.

Turns out that we have MTS with 1 server. The Oracle 8 has MTS with server=0 thus lots of processes. At the moment we only have 120 users going to about 500. Could we have a problem with MTS? Any ideas on number of users per MTS (guideline). We have some large SQL/long running (ERP so we can't change them). Clearly, some slowdown is when people get in at about the same time - no surprise, but even then the cpu is low, disk, scsi low.

Any experience with this?
Thanks

scott fisher Received on Fri Jun 27 2003 - 20:41:13 CDT