Last week I started thinking about goozex.com and what fundamental economic patterns you would see if you had complete access to their trading logs. For those who haven't heard of it, goozex is a trading platform for used game and computer software. Sellers who are looking to unload some goods can go to goozex and get paired up with buyers who are looking for specific game titles.

It may sound like a niche version of eBay, but there are a couple of things that make it interesting. For starters, any transaction between users will always boil down to an exchange of 1 software title for a quantity of goozex points, the trading currency used on the site. The point value of any software title is regulated by goozex, meaning that sellers do not have the ability to set their own prices, and buyers do not have the ability to pay more or less for a given software title.

With such a tight control over the marketplace for specific goods, I'm interested in a couple of things:

1. How quickly do supply and demand react to changes in point value?
2. How quickly does demand increase for a big release? How long does it take to reach a steady level?
3. How long is the trading market for a new title likely to be supply-starved?

MediaTomb is a robust open-source UPnP server that has quickly become an important part of my network. It organizes media in what it calls virtual containers, a fancy but vague term to describe how the media it serves can be organized and displayed according to a hierarchy unrelated to the filesystem on which it resides. This is a great idea, but an abstract hierarchy not defined by the filesystem means that the mediatomb server needs a method for discovering new media and adding it to its database.

Enter Inotify, the new-ish linux kernel feature that allows applications to listen for filesystem events. Mediatomb can be configured to listen for inotify events on interesting directories. This is certainly the only decent way to manage very large media libraries, as the alternative method of periodically rescanning the filesystem for new files is an expensive operation on large or remote libraries.

Using inotify works on simple installations, but it won't work when mediatomb uses NFS or another remote filesystem to access the library. While creating library files on the mediatomb machine itself will go through the kernel VFS layer and generate an inotify event that mediatomb can respond to, changing or creating a file on the NFS server or on any other mounted client will not propagate inotify events to other hosts. Though communicating these remote events appears built in to newer versions of samba, I needed a solution that would work with NFS.

Puppet is a cross-platform system for managing machines. It can manage files, packages, users and anything else that needs managing. The system is composed of a puppetd daemon process running on a client machine, which periodically connects to a remote puppetmaster to download its configuration and apply it. All communication and file transfers between the client and puppetmaster are done via XML/RPC over SSL.

If you'd like to know more about what else puppet can do or how it works, reductivelabs has an excellent introduction. This article will instead focus on how to set up an environment for measuring the throughput of the puppetmaster.

This form will generate a syntactically correct getconfig request that can be sent to a puppetmaster. The request is useful for benchmarking applications that are not ruby-based.

I recently began charting the freefall of the Gentoo Linux distribution. The project peaked in 2003 but has been in steady decline since Daniel Robbins got up from the captains chair. The release history on distrowatch gives a good 30-thousand foot view, showing that the 2008.0 release that recently shipped was the end of a 14 month dry spell since the previous release. In nearly the same time frame the tireless Ubuntu machine continued churning through its 6-month release cycle and shipped two major updates. Even Gentoo Is For Ricers, the preferred depot for anti-gentoo sentiment, has maintained a reverent silence on gentoos inability to get updates out the door.