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Many Sessions Waiting for 'enq: KI - contention' Opening a PDB (Doc ID 2604306.1)

Last updated on DECEMBER 30, 2021

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 12.2 to 18]
Information in this document applies to any platform.


Many sessions are waiting for 'enq: KI - contention'.

1) during concurrent PDB opening becomes longer as #of PDB's or # of instances increases.


2) when "alter system .. add datafile" or datafile relevant command issued. 

The hanganalyze output will show the following or similar hangchain showing the final blocker as idle DBWn:



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