MySQL Bugs: #47572: MySQL Cluster : Multi-exec txns accessing Blobs have high mem usage

Bug #47572	MySQL Cluster : Multi-exec txns accessing Blobs have high mem usage
Submitted:	23 Sep 2009 23:11	Modified:	25 Sep 2009 6:17
Reporter:	Frazer Clement	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Cluster: Cluster (NDB) storage engine	Severity:	S2 (Serious)
Version:	mysql-5.1-telco-6.2	OS:	Any
Assigned to:	Frazer Clement	CPU Architecture:	Any

Description:
When performing a transaction which involves Blobs at some point, and multiple execute() calls at the NdbApi level, MySQLD memory usage increases throughout execution.

How to repeat:
1) Start transaction
2) Access some table with blob data
3) Perform SELECT with joins across tables
4) Generally create as many NdbOperation requests as possible
5) Monitor memory usage

Suggested fix:
Remove current Blob restriction on freeing up completed operations as multi-execute transaction progresses.
Validate success and failure scenarios.

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/84448

3061 Jonas Oreland	2009-09-24
      ndb - bug#47572 - commit/push for club

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/84510

3003 Frazer Clement	2009-09-24
      Bug#47572 Multi-exec txns accessing Blobs have high memory usage.  Allow periodic resource release for Blob transactions
      modified:
        sql/ha_ndbcluster.cc

Pushed to 6.2.19, 6.3.27, 7.0.8, 7.1.0

Documented bugfix in the NDB-6.2.19, 6.3.27, and 7.0.8 changelogs, as follows:

        Large transactions involving joins between tables containing 
        BLOB columns used excessive memory.

Closed.

Pushed into 5.1.37-ndb-6.2.19 (revid:frazer@mysql.com-20090929142503-sst6g3fs0vx9fgil) (version source revid:frazer@mysql.com-20090924141029-deo54v8y443840i3) (merge vers: 5.1.37-ndb-6.2.19) (pib:11)

Pushed into 5.1.37-ndb-6.3.28 (revid:jonas@mysql.com-20090930070741-13u316s7s2l7e1ej) (version source revid:frazer@mysql.com-20090924145421-nu2r7o4sx8imfgfc) (merge vers: 5.1.37-ndb-6.3.27) (pib:11)

Pushed into 5.1.37-ndb-7.0.9 (revid:jonas@mysql.com-20090930075942-1q6asjcp0gaeynmj) (version source revid:frazer@mysql.com-20090924150728-6timxf5546dgg7hs) (merge vers: 5.1.37-ndb-7.0.8) (pib:11)

Pushed into 5.1.35-ndb-7.1.0 (revid:jonas@mysql.com-20090930080049-1c8a8cio9qgvhq35) (version source revid:frazer@mysql.com-20090924150932-93344wrj807ngz09) (merge vers: 5.1.35-ndb-7.1.0) (pib:11)