I’ve been wondering that lately. I’ve been using Subversion for … well … what seems to be a lot of years now. Looking back at the dates for Subversion’s history and coinciding them with events that were happening in my life, I’m guessing that I started using Subversion no later than the end of 2003. (So, maybe that’s not “a lot of years now”…) And I was using CVS from about 2001 until I started with Subversion. During the majority of that time, I have been either the sole commiter of the code base that I was working on, or one of very few people working on the same code.
Recently, I started a job where I’ll likely be working more mingled in with other developers on the same code at the same time. Everything is set up using Subversion. Before starting this new job, though, I began looking into distributed source control, which is the cool new kid on the block. I’ve created some personal projects using Bazaar and have glanced at Darcs, Mercurial, and Git. I like Bazaar a lot. It can be a little sluggish at times (like pushing, pulling, and merging), but not unbearably so - and I expect that it’ll get better. I keep running through my mind how moving to a distributed model would impact the work flow with my co-workers and I’m not totally convinced that distributed is always the way to go.
I just finished reading this piece of a conversation with Linus Torvalds regarding Git, and I remain unconvinced that going distributed would be the best thing for us. And I’m guessing that maybe most small teams of “closed” development probably don’t need a distributed source control system, either. It seems that the problems that have spawned this new model of source control is more of a problem for open source development, particularly of larger projects, and less of a problem for smaller proprietary development. For example, it’s really important for Linus that Linux kernel developers (or anyone, really) be able at any moment to create a new branch. It’s important for Linux that people be able to experiment with new kooky ideas and maybe come up with a cool new feature to go into the kernel. It’s also important to Linus that people be able to do so in anonymity. I can see how this would be important for a project that has potentially tens of thousands of developers interested in experimenting with the code and are doing so on their own free time. I think this is less important when a small team is being paid to work on a code base. Typically, you don’t have the leisure time to perform experiments. If you do need to work on an experimental feature set, it’s not a problem for a repository admin at work to create a branch for you. And anonymity isn’t typically necessary at work. At least, not anywhere I’ve ever worked.
I can see how having an “off-line” repository could be helpful. But from what I’ve heard, svk should address a lot of those issues. And most of these distributed systems are reputed to handle merging between branches better, which would be nice. I love Bazaar and would love to use it at work, but I’m just not convinced that it buys us enough benefits to switch from Subversion. Does anyone have convincing reasons that a small, closed source development team should consider switching to a distributed tool?