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

Last updated on JULY 20, 2024

Applies to:

Oracle Database - Enterprise Edition - Version 12.2.0.1 to 18.9.0.0.0 [Release 12.2 to 18]
Information in this document applies to any platform.

Symptoms

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

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

OR 

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:

 

Cause

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In this Document
Symptoms
Cause
Solution
References

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