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On 12.2, Sessions are Waiting a Long Time with event "enq: UL - Contention" on ctxsys.drvdml.com_sync_index (Doc ID 2481725.1)

Last updated on NOVEMBER 30, 2021

Applies to:

Oracle Text - Version and later
Information in this document applies to any platform.


After upgrading the database to or creating a new 12.2 database, there are lots of sessions waiting a long time with event "enq: UL - contention".

Below is the statement being waited on in those sessions:

begin ctxsys.drvdml.com_sync_index(:idxname, :idxmem, :partname); end;


This is evident from an AWR report taken during the time of contention:


The issue is happening for context indexes created with SYNC (ON COMMIT).


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