Enq: fB-contention

Select wait_class, name from V $ event_name where name = 'enq: fB-contention '; wait_class name

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Other Enq: fB-contention SQL> select name, parameter1, parameter2, parameter3 from V $ event_name where name = 'enq: fB-contention '; Name parameter1 parameter2 parameter3

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Enq: fB-contention name | mode tablespace # DBA
"This is the format block enqueue, used only when data blocks are using assm (automatic segment space management or bitmapped freelists).
We might fail CT, common FB enqueue relate to buffer busy conditions, especially since assm tends to cause performance problems under heavily DML loads ."

Http://www.dba-oracle.com/t_enqueue_wait_types_.htm

 

"Well the format block enqueue (" Enq: FB contention ") is related to grabbing

New blocks in assm tablespaces, during an insert operation for example. It

Might be a good idea at this point to find out what the 'query' is that you

Are actually doing and if it is happening in parallel etc. Incidentally are

Both of these queries on the one system, or is one prod and one UAT? "

Http://www.freelists.org/post/oracle-l/Execution-time-in-SHARED-SERVER-vs-DEDICATED-SERVER-RAC-10gR2,12

Reprinted: http://blog.chinaunix.net/uid-499812-id-3046288.html