ORA-29770: global enqueue process LCK0

ORA-29770 LMHB Terminates Instance as LMON Waited for Control File IO or LIBRARY CACHE or ROW CACHE Event for too Long [ID 1197674.1]

pplies to:

Oracle Server - Enterprise Edition - Version: 11.1.0.6 to 11.2.0.2 - Release: 11.1 to 11.2
Information in this document applies to any platform.

Symptoms

Instance crashes with messages like the following:

Wed Sep 09 03:24:14 2009
LMON (ospid: 31216) waits for event 'control file sequential read' for 88 secs.
Wed Sep 09 03:24:29 2009
Errors in file /oracle/base/diag/rdbms/prod/prod3/trace/prod3_lmhb_31304.trc  (incident=2329):
ORA-29770: global enqueue process LMON (OSID 31216) is hung for more than 70 seconds
Incident details in: /oracle/base/diag/rdbms/prod/prod3/incident/incdir_2329/prod3_lmhb_31304_i2329.trc
Wed Sep 09 03:24:39 2009
ERROR: Some process(s) is not making progress.
LMHB (ospid: 31304) is terminating the instance.
..
ORA-1092 : opitsk aborting process

OR:

Mon Jan 10 14:23:00 2011
LMON (ospid: 8594) waits for event 'control file sequential read' for 87 secs.
Mon Jan 10 14:23:31 2011
LMON (ospid: 8594) waits for event 'control file sequential read' for 118 secs.
ERROR: LMON is not healthy and has no heartbeat.
ERROR: LM** (ospid: 8614) is terminating the instance.

Cause

RAC critical background processes(LMON, LCK0, LMD0 etc) not participating heart beat for longer than default threshold of 70 seconds as it's waiting for control file IO, library cache or row cache waits which could take longer time.

Solution

Fix for bug 8888434 is included in 11.2.0.2, LMHB will not terminate critical RAC background processes if they are waiting for the mentioned events for too long

Fix for bug 11890804 is included in 11.2.0.3, without the fix, LMHB may immediately kill processes that has exceeded the timeout but went into another
wait