Bug #33739 Bug in TUP-SCAN
Submitted: 8 Jan 2008 12:19 Modified: 20 Feb 2008 21:45
Reporter: Jonas Oreland Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Cluster: Cluster (NDB) storage engine Severity:S3 (Non-critical)
Version: OS:Any
Assigned to: Jonas Oreland CPU Architecture:Any
Tags: 5.1->

[8 Jan 2008 12:19] Jonas Oreland
Description:
If TUP-SCAN gets timesliced.
The page is not refetched.

For DD, this can mean that we access incorrect page.
  as it can have been evicted when re-entering

For MM with page-release, this can mean that we access incorrect page.
  as it can have been released when re-entering

How to repeat:
autotest repeats MM-with page release

Suggested fix:
reset state to Get_page on entering scanNext
[8 Jan 2008 12:23] Bugs System
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/40676

ChangeSet@1.2528, 2008-01-08 13:23:35+01:00, jonas@perch.ndb.mysql.com +1 -0
  ndb - bug#33739
    page need to refetched after timeslice
[8 Jan 2008 13:20] Bugs System
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/40681

ChangeSet@1.2829, 2008-01-08 14:21:17+01:00, jonas@perch.ndb.mysql.com +1 -0
  ndb - bug#33739
    Additional fix for bug#33739 (63 and upwards)
    reset realpid_mm to cater for page being released
[8 Jan 2008 13:27] Jonas Oreland
pushed to 51-telco-gca, 51-ndb, telco-6.1, telco-6.2, telco-6.3, telco-6.4
[2 Feb 2008 12:03] Jon Stephens
Documented in 5.1.23-ndb-6.2.11 and 5.1.23-ndb-6.3.8 changelogs as follows:

        Some tuple scans caused the wrong memory page to be accessed,
        leading to invalid results. This issue could affect both
        in-memory and Disk Data tables.

Left bug status as PQ, pending additional merges.
[20 Feb 2008 16:02] Bugs System
Pushed into 5.1.24-rc
[20 Feb 2008 16:04] Bugs System
Pushed into 6.0.5-alpha
[20 Feb 2008 21:45] Jon Stephens
Also documented for 5.1.24 and 6.0.5.