When your system is busy and you issue:

ORADEBUG DUMP SYSTEMSTATE 10 

to try to diagnose a problem, frequently it core dumps and generates an     
incomplete system state dump.  You may also have this problem with other 
oradebug commands, like "DUMP CONTEXTAREA 1".  This is a generic (not port 
specific) problem.


Solution Description: 
===================== 
 
This problem is seen in pre 8.0.6 releases.  It is also seen in 8i
when you use Server Manager (svrmgrl).  It is fixed in 8.0.6.

For releases prior to 8.0.6 (or in 8i using oradebug in svrmgrl) simply 
select * from dual before before running the systemstate dump command.

For 8i you can also run oradebug from SQL*Plus.
 
Explanation: 
===================== 
Connect as INTERNAL when you run oradebug.   "Connect internal" 
creates a dummy or incomplete process state.  The buffer dump routines attempt 
to get the hash latch for the buffer it is attempting to dump.  While getting 
a latch it refers to a process state which is not available and core dumps. 

The select * from dual forces the process state object to be completed so 
that the subsequent systemstate dump command completes.