Bug #40734 Initial creation redo-log-files can be slow on some os/hw combinations
Submitted: 14 Nov 2008 11:10 Modified: 14 Nov 2008 14:07
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

[14 Nov 2008 11:10] Jonas Oreland
Description:
when writing initial redo-log-files,
the writes are performed using sync,
this cause very very slow io on some os/hw combinations

How to repeat:
start ndb :-)

Suggested fix:
write wo/ sync, and then sync file when closing it
[14 Nov 2008 11:13] 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/58761

2737 Jonas Oreland	2008-11-14
      ndb - bug#40734 - only sync redo-files at end during initial redo creation
[14 Nov 2008 11:17] Bugs System
Pushed into 5.1.29-ndb-6.4.0  (revid:jonas@mysql.com-20081114111753-0tfcc2to1fsq0d9b) (version source revid:jonas@mysql.com-20081114112117-mazijdv8mdxtso7r) (pib:5)
[14 Nov 2008 11:17] Bugs System
Pushed into 5.1.29-ndb-6.2.17  (revid:jonas@mysql.com-20081114111753-0tfcc2to1fsq0d9b) (version source revid:jonas@mysql.com-20081114111753-0tfcc2to1fsq0d9b) (pib:5)
[14 Nov 2008 11:18] Bugs System
Pushed into 5.1.29-ndb-6.3.19  (revid:jonas@mysql.com-20081114111753-0tfcc2to1fsq0d9b) (version source revid:jonas@mysql.com-20081114111935-evdvbapq4q3d6p73) (pib:5)
[14 Nov 2008 14:07] Jon Stephens
Documented in the NDB-6.2.17 and NDB-6.3.18 changelogs as follows:

        Redo log creation was very slow on some platforms, causing MySQL Cluster
        to start more slowly than necessary with some combinations of hardware
        and operating system. This was due to all write operations being
        synchronized to disk while creating a redo log file. Now this
        synchronization occurs only after the redo log has been created.
[12 Dec 2008 23:26] Bugs System
Pushed into 6.0.9-alpha  (revid:jonas@mysql.com-20081114111753-0tfcc2to1fsq0d9b) (version source revid:tomas.ulin@sun.com-20081209185954-9svcixh2p5hsfi6w) (pib:5)