July 2006 – David's Blog

A critical tool in a programmer’s chest includes a version control system (VCS) to keep track of software changes. I was initially going to install the Subversion VCS for my new projects, but decided to look around for other alternatives. Over the past couple of days I have found out that there is a lot of activity going on in this historically stagnant part of computing.

My search for alternative version control systems (VCS) started after I had successfully hacked my NSLU2 network appliance so that I could install on it a very popular open-source VCS called Subversion. I managed to get everything installed, however, during configuration I began to have doubts about using it. There were more setup options for Subversion than I wanted to mess with and, with every one, I had to go a little deeper to fully understand how the system worked so that I knew how I wanted it to work. I had been hoping for something more plug-n-play because I’m probably going to be the only person using it. Thus began the hunt for other alternatives.

While poking around the ‘Net, I had run across several different open-source projects focusing on version control, but didn’t really think much of them. Of the names I did see, none stuck out like CVS and Subversion; after all, they were the only real version control systems, right?

Guess again! As I dug deeper I was surprised to find that there is a lot of activity going on in the world of version control. I found over ten different projects all involved in developing what you might call a “modern” version control system! Some of them are Bazaar-NG, DARCS, Monotone, Arch, Git/Cogito, Codeville, Mercurial, and SVK.

The main idea behind many of these new systems is to change the repository model from having a central repository and server to a distributed one where every “checkout” of the source code can be its own repository and server, thus imparting the name of distributed version control systems (DVCS). One of the interesting aspects of these new systems is that they give software developers more flexibility in how they can share code amongst themselves.

Of the projects which I found, I’ve narrowed my options to three: DARCS, Mercurial, and Bazaar-NG. I’ll tell you more about what I decide later, but I will leave you with some of the important pages that I read.

h3. Resources

Project sites
• “http://bazaar-vcs.org/”:http://bazaar-vcs.org/
• “http://darcs.net/”:http://darcs.net/
• “http://www.selenic.com/mercurial/”:http://www.selenic.com/mercurial/

Thoughts from others
• “http://jaortega.wordpress.com/tag/version-control/”:http://jaortega.wordpress.com/tag/version-control/
• “http://blog.ianbicking.org/dvcs-mini-roundup.html”:http://blog.ianbicking.org/dvcs-mini-roundup.html (don’t miss the comments)
• “http://mark.stosberg.com/Tech/darcs/cvs_switch/index.html”:http://mark.stosberg.com/Tech/darcs/cvs_switch/index.html

Comparisons
• “http://better-scm.berlios.de/comparison/comparison.html”:http://better-scm.berlios.de/comparison/comparison.html
• “http://zooko.com/revision_control_quick_ref.html”:http://zooko.com/revision_control_quick_ref.html
• “http://bazaar-vcs.org/RcsComparisons”:http://bazaar-vcs.org/RcsComparisons

When I received the hard drive I put it in my FireVue, an external firewire enclosure I bought many moons ago from a company called Granite Digital.

…The punch-line to this story is that all computers and hard drive hardware having a controller based on a communication protocol known as ATA-5 can only address up to 128Gb of data (or 137Gb, depending on if you say toh-may-toh or toh-mah-toh).

…A newer drive protocol called ATA-6 has been out for a few years and current hardware based on this version can address as much as 2 terabytes of information! … Because this is a newer protocol there is a lot of computer hardware out there which has this 128Gb issue, including my beloved FireVue which I purchased around 2001.

…Looking at Apple’s web page on PowerMac specifications, I can see that Harold, my ‘newest’ computer, was first introduced in September 1999 and was phased out 1 year later; this was well before the June 2002 cutoff.

…After I purchased the software, a quick installation and a reboot I could instantly see the larger drive on my computer and Disk Utility didn’t have any more issues formating or partitioning the drive.

…After I installed it, my computer could see all 250Gb, but Disk Utility still couldn’t format or partition the hard drive.

…As it turns out, the older enclosures based on ATA-5 can see hard drives larger than 128Gb using their firmware update.

…So, I’m going to move my smaller drives to the two swappable trays that I have for my firewire enclosure, put my two large drives inside of my PowerMac and rely on the ATA-6 software to do it’s thing.