Database Hang and Users Cannot Login; Errors in the Alert Log 'ORA-00494: enqueue [CF]'
(Doc ID 2351185.1)
Last updated on FEBRUARY 08, 2022
Applies to:Oracle Database - Enterprise Edition - Version 22.214.171.124 and later
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 Cloud Exadata Service - Version N/A and later
Information in this document applies to any platform.
- Database hang and users cannot connect
- Alert log has CF enqueue error:
ORA-00494: enqueue [CF] held for too long (more than 900 seconds) by 'inst 1, osid 3106'
- AWR shows high I/O waits:
- Waits by total wait time shows top wait as user I/O:1
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