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LMS Processes Failed With ORA-600 [Kclexpandlock_1] on Index Only table. (Doc ID 1178684.1)

Last updated on OCTOBER 01, 2019

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 10.2]
Information in this document applies to any platform.
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This problem was observed on Oracle
It occurred on a two node RAC database.

Following a platform migration one of two RAC instances failed with below error in the alert log:

ORA-00600: internal error code, arguments: [kclexpandlock_1], [449794], [], [], [], [], [], []
LMSu: terminating instance due to error 484
ORA-00484: LMS* process terminated with error
Termination issued to instance processes. Waiting for the processes to exit
Instance terminated by LMSu, pid = <PID>

The call stack in the trace file includes functions like:

... kcbassertb1 kclexpandlock kjbmpocr kjmxmpm kjmpmsgi kjmsm ksbrdp opirip opidrv sou2o opimai_real main

Referenced object 449794 is an index (PK_INDEX_NAME) and is an IOT object:



The error is more likely to occur after a lot of DML on IOT tables. It is also more likely after performing a shrink operation on IOT tables.


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