I started considering the idea of using Superfeedr well over six months ago, but still had concerns about their stability and viability – ultimately I got over that and realized that I need to outsource this part of chi.mp. This week I finally pushed out code for chi.mp that uses SuperFeedr’s PubSubHubBub hub to receive feed updates. Initially I used their XMPP interface, however after repeated encouragement from Julien @ Superfeedr I made the switch over to PubSubHubBub with only a small amount of work.

I still have to move a bunch of feeds over to use Superfeedr but I feel at least part of the burden of managing all of these various feeds beginning to leave my shoulders, and for that I am very thankful.

As part of the troubleshooting process we decided to hook up a profiler. I started out looking at the profiler that’s built into JRuby (use the –sample option) and got a little bit of data. Urged on by @dje I started looking at Java profilers. It’s been a while since I’ve dug into the world of Java so I started with open source tools to get my bearings. Suffice to say I did not find what I was looking for there, so I did what any self-respecting Internet-savvy being would do in my place: I twittered it.

Thanks to @sethladd I downloaded YourKit, got it hooked up in about 30 minutes with the production system and away I went. The results so far have been promising. Some of the issues that could be fixed have, however we are basically at a point where we’ve run into a wall with Ruby’s Net::HTTP implementation. The long term solution is probably to replace the Net::HTTP library with something based on the Reactor pattern (see my jruby-http-reactor project for the initial baby-steps in that direction) but the bottom line is without a profiler to help us get headed on the right path we probably would have spent a lot more time “fixing” things that weren’t broken. If you’re considering using JRuby consider that you will have access to a wide variety of Java tools that can be quite helpful when troubleshooting.