Skip to main content

Switching version control systems

We have been using GNU arch the last couple of years as a version control system, however Tom Lords' implementation does not scale well, and some of our software packages have 10 thousands of commits. This means that a single commit operation may take _minutes_. It is awful to wait so much time for a single commit, and it really degrades productivity.

I was considering Mercurial, Bazaar-NG and git, however this was not an easy decision, as the "modern" version control systems promote the use of branches over anything else, and our current version control model relied on cherry-picking heavily:
  • developer commits the solution for each bug separately to his/her branch
  • QA people pick patches from developer branches and integrate them to a 'test' branch, once the test was successful,
  • release manager picks patches from the 'test' branch and integrates to mainline, if he doesn't find anything odd during review
This worked wonderfully in GNU arch, but new VC systems lack in this area. Bazaar has no cherry picking support at all, Mercurial has some incomplete support with a plugin named transplant, git has cherry picking, but that relies on heuristics (it guesses whether a patch was integrated by using a checksum of the patch).

I was considering to change the process I outlined above, but I'm not sure how that would work out. We sometimes need to work with people not really experienced with VC systems at all, asking them to manage their own branches for each bugfix/problem group seems to raise the bar a bit too high.

Nevertheless git seemed to have solutions for both worlds (e.g. picking patches AND merging branches), so I choose git over the other two, and now I converted some of the syslog-ng history to git in order to gather some real-life experience.

I like what I see so far, git 1.5.x is really way better than older versions on the usability and documentation front. I now feel comfortable enough with git as I could finally understand the working model and the structure of the git history.And git is fast like lightning :)

Comments

Post a Comment

Popular posts from this blog

syslog-ng fun with performance

I like christmas for a number of reasons: in addition to the traditional "meet and have fun with your family", eat lots of delicious food and so on, I like it because this is the season of the year when I have some time to do whatever I feel like. This year I felt like doing some syslog-ng performance analysis. After reading Ulrich Deppert's series about stuff "What every programmer should know about memory" on LWN, I thought I'm more than prepared to improve syslog-ng performance. Before going any further, I'd recommend this reading to any programmer, it's a bit long but every second reading it is worth it. As you need to measure performance in order to improve it, I wrote a tool called "loggen". This program generates messages messages at a user-specifyable rate. Apart from the git repository you can get this tool from the latest syslog-ng snapshots. Loggen supports TCP, UDP and UNIX domain sockets, so really almost everything can be me
17 comments
Read more

syslog-ng roadmap 2.1 & 2.2

We had a meeting on the syslog-ng roadmap today where we decided some important things, and I thought I'd use this channel to tell you about it. The Open Source Edition will see a 2.1 release incorporating all core changes currently in the Premium Edition and additionally the SQL destination driver. We are going to start development on the 2.2 PE features, but some of those will also be incorporated in the open source version: support for the latest work of IETF syslog protocols unique sequence numbering for messages support for parsing message contents Previously syslog-ng followed the odd/even version numbering to denote development/stable releases. I'm going to abandon this numbering now: the next syslog-ng OSE release is going to have a 2.1 version number and will basically come out with tested code changes only. The current feature set in PE were developed in a closed manner and I don't want to repeat this mistake. The features that were decided to be part of the Open
12 comments
Read more

syslog-ng 3.0 and SNMP traps

Last time I've written about how syslog-ng is able to change message contents. I thought it'd be useful to give you a more practical example, instead of a generic description. It is quite common to convert SNMP traps to syslog messages. The easiest implementation is to run snmptrapd and have it create a log message based on the trap. There's a small issue though: snmptrapd uses the UNIX syslog() API, and as such it is not able to propagate the originating host of the SNMP trap to the hostname portion of the syslog message. This means that all traps are logged as messages coming from the host running snmptrapd, and the hostname information is part of the message payload. Of course it'd be much easier to process syslog messages, if this were not the case. A solution would be to patch snmptrapd to send complete syslog frames, but that would require changing snmptrapd source. The alternative is to use the new parse and rewrite features of syslog-ng 3.0. First, you need to f
2 comments
Read more