My Oracle Support Banner

'Library Cache Lock' (Cycle) Seen During DataPump Import in 12.2 RAC Environment (Doc ID 2407491.1)

Last updated on APRIL 05, 2023

Applies to:

Oracle Database Cloud Schema Service - Version N/A and later
Gen 1 Exadata Cloud at Customer (Oracle Exadata Database Cloud Machine) - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Exadata Express Cloud Service - Version N/A and later
Oracle Database Backup Service - Version N/A and later
Information in this document applies to any platform.

Symptoms

NOTE: The document content below, the user information and data used represents fictitious data from the Oracle sample schema(s) or Public Documentation delivered with an Oracle database product. Any similarity to actual persons, living or dead, is purely coincidental and not intended in any manner.

High waits and signifiant performance degradation are seen due to 'library cache lock' (cycle)<='library cache lock' for DataPump Worker (DW) processes.
The issue is seen when running DataPump import with parallel>1 in a RAC environment during the metadata load operation.

A system state dump gathered during the issue time, shows the hang is due to 'library cache lock' (cycle)<='library cache lock' deadlock:


The deadlock can be seen when loading any of the following object type: constraints, index, function, procedure, package, role_grant and view, even if the impdp job is started with CLUSTER=N.

Changes

The DataPump issue is observed after upgrade to 12.2, only in RAC environment.


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
Changes
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.