A while ago we succeeded in upgrading the Debian server where I keep many of my SVN repositories. (The server was running on “testing”, but we hadn’t dared to upgrade it for a long time until it came time to make it “stable” again with Lenny.) On of the upgraded packages in Lenny is Subversion, now at 1.5.1, which means that I can finally start using subversions new merge tracking features.
To be able to use merge tracking for my existing repositories, I first have to upgrade these. From the svn 1.5 release notes:
The Subversion 1.5 server works with 1.4 and older repositories, and it will not upgrade such repositories to 1.5 unless specifically requested to via the svnadmin upgrade command. This means that some of the new 1.5 features will not become available simply by upgrading your server: you will also have to upgrade your repositories. (We decided not to auto-upgrade repositories because we didn’t want 1.5 to silently make repositories unusable by 1.4 — that step should be a conscious decision on the part of the repository admin.)
The only other machine I’m using these repos from is my laptop, which, running Gentoo, is already at Subversion 1.6.2. So, how do I upgrade?
First, I made a backup of all our SVN repos using a script that Halfgaar made to run from cron. After running that script, I initialized the upgrade procedure:
cd /var/svn svnadmin upgrade blog.bigsmoke.us svn-populate-node-origins-index blog.bigsmoke.us
The last command is unimportant, but may speed up the next few operations. The release notes again:
After running svnadmin upgrade, you may wish to also run the svn-populate-node-origins-index program on the repository. Subversion 1.5 maintains a node-origins index for each repository, and builds the index lazily as the information is needed. But for old repositories with lots of revisions, it’s better to create the index in one step, using the aforementioned tool, than to have live queries be slower until the index has built itself. See issue #3024 for details.
With my data safe and the repo upgraded, it’s time to actually test the new merge tracking features:
cd ~/blog.bigsmoke.us # Enter working copy (on the same server) # I'm now in the lichtgekruid branch. svn switch file:///var/svn/blog.bigsmoke.us/trunk svn add wp-content/plugins/openid svn ci -m "I was convinced this was a change which didn't belong to my feature branch" wp-content/plugins/openid svn switch file:///var/svn/blog.bigsmoke.us/branches/lichtgekruid svn merge file:///var/svn/blog.bigsmoke.us/trunk # The last command was a real kicker, not having to find and specify the correct range of revision numbers. svn ci -m "Merged changes from trunk to 'lichtgekruid' branch." svn switch file:///var/svn/blog.bigsmoke.us/trunk svn merge file:///var/svn/blog.bigsmoke.us/branches/lichtgekruid # (Another spontaneous orgasm.) svn ci -m "Merged 'lichtgekruid' branch back into trunk."
Ok, I know I could have simply changed all these projects to use Git, and I like Git. I love its simplicity and flexibility. But, call me old-fashioned; I have an SVN fetish, and so far I find its merge tracking quite convincing.