My Oracle Support Banner

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

Last updated on JUNE 22, 2020

Applies to:

Oracle Database - Enterprise Edition - Version 18.1.0.0.0 to 19.7.0.0.0 [Release 18 to 19]
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 data file relevant command issued 


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

 

Cause

To view full details, sign in with your My Oracle Support account.

Don't have a My Oracle Support account? Click to get started!


In this Document
Symptoms
Cause
Solution
References

My Oracle Support provides customers with access to over a million knowledge articles and a vibrant support community of peers and Oracle experts.