"Null Event" Session Wait - hung Sessions

Hi,

I am running a Production 9.2.0.1 Instance on AIX 64bit.

I am encountering sessions on a frequent basis that appear be hung, not taking any apparent CPU nor I/O. All I can seem to see in V$SESSION_WAITS is wait time increasing against event "NULL Event".

As anyone encountered this ? What does it mean ? I cannot find details about it's
meaning or how to stop it. I have tryed dumping the trace for the session but nothing gets written to the dump directory - I have trying DBMS_SYSTEM.set_Ev
and also ORADEBUG but get nought !

These sessions are connecting via JDBC Thin driver - not sure if this is significant or not.

Any help would be much appreciated.

Regards
Martin Received on Fri Feb 07 2003 - 11:09:04 CST