Tag Archives: memory

EXPLAIN PLAN shared memory

Recently I did an investigation of an ORA-04031 which happens almost regularly on a Oracle database server with 9G of memory allocated to shared pool and disabled Automatic Shared Memory Management (sga_target=0). The problem query is a report that is a very big SQL query – more than 200K of plain text. The exact error message is “ORA-04031: unable to allocate 235704 bytes of shared memory (“shared pool”,”select * from (…”,”Typecheck”,”qry_text : qcpisqt”)”. Here I’ll briefly describe what I did to identify root cause of the error and will talk about one interesting detail of the EXPLAIN PLAN as it was used to reproduce the issue.

Continue reading

“java.lang.OutOfMemoryError: unable to create new native thread” in WLS

Recently I’ve struggled with subj. One of the customers of the company I’m working has encountered several “java.lang.OutOfMemoryError: unable to create new native thread” appearances in a clustered WebLogic Server 9 environment. Here I’ll describe why it could happen and possible workarounds for this error.

Continue reading