Why you should go to conferences

One thing I like about working in a large corporation is that you get to meet all sorts of interesting people. You actually have to meet them, since you can't get anything done without coordinating with a whole bunch of them. But since this tends to get nothing done most of the time, I chose to work in a small company instead. Here if you want to do anything, you probably have to do it yourself (there are some interesting repercussions of this that I will leave for a future post). Now, if you work in a small company and want to meet lots of interesting people, you basically have three two options:

1. Use the net - blogs, mailing lists, newsgroups, twitter, friendfeed, etc. (done that)
2. Attend conferences.
3. Go to parties.

Now as you can personally attest to, I've got No.1 covered. So the last couple of days I worked on number 2 instead. The nice guys at ellak.gr organized the 3rd FLOSS conference and since it took place very close to where I work, I took the opportunity to avoid working meet some old friends and make some new ones.

Number One of course, is Wietse Venema. Since his work was an inspiration for me to pursue a PhD in computer security, I just had to see him in person once. He was more fun that I expected, to be honest. Security guys have a reputation of being a wee bit paranoid and itsy-bitsy abrupt on normal people, not to mention complete strangers. Wietse however was neither. This probably has to do with his academic background or maybe the fact that he is Dutch, who knows. He proved to be a warm, funny guy instead, who runs FreeBSD on his laptop (that always shows character in my book).

His talk was about Open Source and Security, both matters dear to my heart. The discussion of Postfix was a walk down memory lane for me. I can still remember the excitement around its initial release: "Hooray! No more sendmail exploits!". Wietse briefly discussed the architecture of postfix and how it relates to its security. He also showed some statistics comparing postfix to sendmail and qmail that I had seen in the past, but was curious to where everyone currently stands. Apparently postfix holds the second place in number of deployments (good), the first in number of lines of code (bad), but that is caused by having reached sendmail's feature list, without compromising the original architectural goals (good). For the problem of security at large, the most provocative suggestion was to make software development too hard for the laymen, so only experts could do it. Heh. As John Wayne so eloquently used to put it: "that'll be the day".

Lots of comparisons were presented in the talk by Diomidis Spinellis, titled A Tale of Four Kernels. The talk covered a code quality comparison of four major commercial and open-source operating systems, Windows, Solaris, Linux and FreeBSD. Diomidis is a well known author and FreeBSD commiter, and that was evident in the quality of his work and presentation. The room was packed, and the Q&A session lasted almost as long as the presentation itself. I suppose the sensitivity of the subject had something to do with it. Diomidis went through heaps of information so fast you could barely comprehend each slide, unless you had the forethought to study his paper before the conference, like your truly did. Although he was very delicate in his conclusions, stating that all systems had comparable quality, there were some members of the audience that seemed to have already made up their minds and didn't care for diplomacy.

Another great talk was by Jim Blandy. The talk was about Open Source Infrastructure for Software Development, which covered the evolution of version control systems (VCS), from SCCS, to the recent crop of distributed VCS. Being one of the people who gave us CVS and Subversion, his recollection of the history of this area was very exciting. Besides sharing some colorful historical tidbits, he also gave a meaningful comparison of the algorithms and data structures used by the various systems. He gave high marks to Subversion for being a fine choice in a centralized organization structure, but eloquently presented the fundamental paradigm shift that distributed VCS present. He said (as best as I can remember) that controlling access to the commit step (what all centralized VCS do) is the wrong (worst?) place to do it, since adding a change is not that big a deal. Instead the point of merging is what should be guarded, since that is when another changeset gets incorporated in our code. The fact that distributed VCS replicate whole repositories, not just working copies, makes allowing commits a natural thing, while making merge selection part of the release engineering process. I've read many pro-distributed-VCS arguments, but I found Jim's focus on the social aspect of the merge process a refreshing one. Luckily, most of my cohorts were present in this talk, so switching our team to Mercurial might not be just a dream after all.

Jim currently works on Mozilla, on the new ActionMonkey JavaScript engine. Since that work was outside the scope of this talk, I managed to corner Jim afterwards to find out more about its current status. The project attempts to integrate the current Mozilla JavaScript engine, SpiderMonkey, with the Tamarin engine contributed by Adobe. The plan was to replace various parts of the old engine with the new ones, like the garbage collector, the JIT compiler, etc. However doing so leads to performance regressions in some areas and Jim said that one lesson they have learned is that if you ship with worse performance, no matter how rare the circumstances that expose it, you will pay for it at some point. String manipulation appears to be one of those areas, since the old engine had been carefully optimized during all this time and achieving the same performance with the new one, requires work. I have been wondering for some time now whether SpiderMonkey uses some variation of the Ropes data structure for String representation, but Jim explained to me that was not the case.

He was also very excited about the experimental tracing JIT that they are working on, that appears to be a perfect fit for dynamic languages and is expected to boost JavaScript performance on future versions of the browser. I told him that I had already heard of it from Steve Yegge, and I've been meaning to read the literature Real Soon Now(TM), which I swear is the truth, the whole truth and nothing but the truth. After I finish this belated post of course. Jim said that Steve is a great story-teller, which means that Steve, if you ever find yourself in Athens and want a free dinner, just let me know. Explaining the benefits of tracing JIT led us to a detour into LISP-land and while Jim has written a Scheme compiler, I've only done LISP programming for a class as a student. Which is another way of saying I didn't understand a word he said, alas. Anyway, the cool things they are working on will probably come to us in firefox 4, so I still have time to get up to speed.

All in all, the conference was quite an enjoyable experience. Old friends, new friends, free food, stimulating discussions, what's more to ask?

What? To be on TV? Hey, that's easy. You just have to hang outside the main conference room chatting with random people, until you notice a cameraman and a journalist taking interviews from conference organizers and speakers. Then you make sure to be in the camera frame and voilà! You've got your 3 seconds of fame.