Bug #43752 ndb: spurious event operation ref count mismatch during nodre restart

Submitted:	19 Mar 2009 16:49	Modified:	20 Mar 2009 9:53
Reporter:	Tomas Ulin	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Cluster: Replication	Severity:	S3 (Non-critical)
Version:	cluster 6.3	OS:	Any
Assigned to:	Tomas Ulin	CPU Architecture:	Any

Description:
When creating/altering table an ndb event operation is created in the mysqld to monitor the table changes for subsequent logging in the binlog.  If create/alter happens during node restart there is a chance that the reference count on the event operation may be wrong.  In debug compile this results in an assert in the ndbapi.

How to repeat:
test_event -n SubscribeNR t1

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/69846

2908 Tomas Ulin	2009-03-19
      Bug #43752  ndb: spurious event operation ref count mismatch during node restart.  Rewrite refcounting code to use gci numbers to determine when an event operation object can be dropped
      modified:
        storage/ndb/include/kernel/signaldata/SumaImpl.hpp
        storage/ndb/src/kernel/blocks/dbdict/Dbdict.cpp
        storage/ndb/src/kernel/blocks/suma/Suma.cpp
        storage/ndb/src/ndbapi/NdbDictionaryImpl.cpp
        storage/ndb/src/ndbapi/NdbEventOperationImpl.cpp
        storage/ndb/src/ndbapi/NdbEventOperationImpl.hpp
        storage/ndb/test/ndbapi/test_event.cpp

Pushed into 5.1.32-ndb-6.3.24 (revid:tomas.ulin@sun.com-20090319165119-a78hjcd8n3nkqx0s) (version source revid:tomas.ulin@sun.com-20090319165056-3t0mu59npkvvtk6d) (merge vers: 5.1.32-ndb-6.3.24) (pib:6)

Pushed into 5.1.32-ndb-7.0.5 (revid:jonas@mysql.com-20090320083640-42c4bviok9ovglwd) (version source revid:jonas@mysql.com-20090320083640-42c4bviok9ovglwd) (merge vers: 5.1.32-ndb-7.0.5) (pib:6)

P2 mainly due to autotest failure and code cleanup
otherwise P3/P4

Documented in the NDB-6.3.24 and 7.0.5 changelogs as follows:

        When creating or altering a table an NdbEventOperation is
        created in the mysqld to monitor the table for subsequent
        logging in the binlog. If this happened happens during a node
        restart there was a chance that the reference count on this event
        operation object could be incorrect, which could lead to an 
        assert in debug MySQL Cluster builds.

Page generated in 0.042 sec. using MySQL 8.4.7-u6-cloud

Timestamp references displayed by the system are UTC.
Content reproduced on this site is the property of the respective copyright holders.
It is not reviewed in advance by Oracle and does not necessarily represent the opinion of Oracle or any other party.