[svn.haxx.se] · SVN Dev · SVN Users · SVN Org · TSVN Dev · TSVN Users · Subclipse Dev · Subclipse Users · this month's index

RE: sync bug -> corrupted proxy repo

From: Jon Foster <Jon.Foster_at_cabot.co.uk>
Date: Wed, 13 Jan 2010 13:12:53 -0000

Hi,

Andersen, Krista [mailto:Krista.Andersen_at_itg.com] wrote:
> Twice I have seen one of my proxy repositories become corrupted due
> to an apparent bug in the svnsync sync process. Has anyone else
> seen this type of behavior from Subversion?

This is probably caused by issue 3546 [1][2]. This is a race
condition - if you have several sync processes running at the same
time then the mirror can get corrupted. You had three commits which
were 1 second apart, so your hook script started 3 copies of svnsync
within 2 seconds. I think this is the first practical report of this
bug; previous discussion was theoretical.

> Here is a comparison the output of the svn log -v for the offending
> revisions (324,325) on both the corrupted and non-corrupted proxy
> repo.

It looks like rev 323 got mirrored twice (as mirror revs 323 and 324),
then rev 324 was mirrored (as mirror rev 325).

> I am a bit concerned about the stability of Subversion since this
> is the second time in two months that I have had to fix this issue.
> Is there a patch or something to prevent this in the future?

Suggested workaround: Change your hook scripts to use the lockf or
lockfile tools[3] to ensure that only one instance of svnsync runs
at once.

Kind regards,
 
Jon

[1]
http://mail-archives.apache.org/mod_mbox/subversion-dev/200911.mbox/%3C2
0091127115356.GC9302_at_jack.stsp.name%3E

[2] http://subversion.tigris.org/issues/show_bug.cgi?id=3546

[3]
http://mail-archives.apache.org/mod_mbox/subversion-dev/200911.mbox/%3C2
0091127132659.GE9302_at_jack.stsp.name%3E

**********************************************************************
This email and its attachments may be confidential and are intended solely for the use of the individual to whom it is addressed. Any views or opinions expressed are solely those of the author and do not necessarily represent those of Cabot Communications Ltd.

If you are not the intended recipient of this email and its attachments, you must take no action based upon them, nor must you copy or show them to anyone.

Cabot Communications Limited
Verona House, Filwood Road, Bristol BS16 3RY, UK
+44 (0) 1179584232

Co. Registered in England number 02817269

Please contact the sender if you believe you have received this email in error.

**********************************************************************

______________________________________________________________________
This email has been scanned by the MessageLabs Email Security System.
For more information please visit http://www.messagelabs.com/email
______________________________________________________________________
Received on 2010-01-13 14:14:49 CET

This is an archived mail posted to the Subversion Users mailing list.