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

Re: SVN Update/Commit Concurrency

From: Ulrich Eckhardt <eckhardt_at_satorlaser.com>
Date: Thu, 10 Jan 2008 10:29:36 +0100

Note up front: I didn't actually look at the sources, so I might be wrong.

On Thursday 10 January 2008, Daniel Becroft wrote:
> What is the method that SVN uses to control commits that happen during
> another user's update?
> For example, in the following scenario:
> 1. [UserA] svn update (HEAD is 100).
> 2. [UserB] svn commit (HEAD is 101) - happens while UserA's update is
> happening
> When UserA's update has completed, will the working copy revision number be
> 100, or 101?

It will be 100.

> I'm guessing that the first thing that the 'svn update' would do is to get
> the HEAD revision and store that, so it becomes a 'svn update --revision
> 100' command?

Right. The first thing is probably that it determines the head revision. From
then on, even if the head revision changes, the revision itself doesn't (they
are treated as almost immutable) so these changes don't affect the ongoing
read operation.

> I've attempted to replicate this situation without success - I can't seem
> to make UserA's update go long enough.

Throttle the network. ;)

Just wondering, but what do you need this info for?


ML: http://subversion.tigris.org/mailing-list-guidelines.html
FAQ: http://subversion.tigris.org/faq.html
Docs: http://svnbook.red-bean.com/
Sator Laser GmbH
Geschäftsführer: Michael Wöhrmann, Amtsgericht Hamburg HR B62 932
           Visit our website at <http://www.satorlaser.de/>
Diese E-Mail einschließlich sämtlicher Anhänge ist nur für den Adressaten bestimmt und kann vertrauliche Informationen enthalten. Bitte benachrichtigen Sie den Absender umgehend, falls Sie nicht der beabsichtigte Empfänger sein sollten. Die E-Mail ist in diesem Fall zu löschen und darf weder gelesen, weitergeleitet, veröffentlicht oder anderweitig benutzt werden.
E-Mails können durch Dritte gelesen werden und Viren sowie nichtautorisierte Änderungen enthalten. Sator Laser GmbH ist für diese Folgen nicht verantwortlich.
To unsubscribe, e-mail: users-unsubscribe_at_subversion.tigris.org
For additional commands, e-mail: users-help_at_subversion.tigris.org
Received on 2008-01-10 10:31:02 CET

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

This site is subject to the Apache Privacy Policy and the Apache Public Forum Archive Policy.