My Oracle Support Banner

Database Crashes With ORA-00494 (Doc ID 753290.1)

Last updated on JANUARY 30, 2022

Applies to:

Oracle Database Cloud Schema Service - Version N/A and later
Oracle Database Exadata 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.


Database may crash with the following error in the alert file (in 11g xml format):

This error can also be accompanied by ORA-600 [2103] which is basically the same problem - a process was unable to obtain the CF enqueue within the specified timeout (default 900 seconds).

This behavior can be correlated with server high load and high concurrency on resources, IO waits and contention, which keep the Oracle background processes from receiving the necessary resources.

Call stack
[01]: kjdgpstackdmp []<-- Signaling
[02]: kjdglblkrdmpint []
[03]: ksikblkrdmp [KSI]
[04]: ksqgtlctx [VOS]
[05]: ksqgelctx [VOS]
[06]: kcc_get_enqueue []
[07]: kccocx []
[08]: kcc_begin_txn_internal []
[09]: krsaibcx []
[10]: kcrrcrl_dbc []
[11]: kcrrcrlc []
[12]: kcrrwkx []
[13]: kcrrwk []
[14]: ksbcti [background_proc]
[15]: ksbabs [background_proc]
[16]: ksbrdp [background_proc]
[17]: opirip []
[18]: opidrv []
[19]: sou2o []
[20]: main []
[21]: _start []

In the System State Dump you can find this short stack


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

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