Archive for the ‘tips’ category

Java Tuning for VuFind

August 1, 2007

Had a few more notes on running VuFind.

Java Tuning

Something that is generally looked over when setting up a Java application is tuning Java. This can be a very daunting endeavor as you generally see tutorials that reference things like interpreting p-values and power analysis. However, if you’re just wanting to set an application up, this is a much larger investment of time and effort that is really needed. So, here are some things you probably want to do.

To set the Java ergonomics for server applications, you simple set a new environmental variable. For Tomcat, this is the CATALINA_OPTS. For development boxes, I tend to make these global variables, but as long as the user account that’s running VuFind’s Tomcat instance has CATALINA_OPTS defined, you’ll see the performance boost.

For those who can’t wait, this is what I set for my instance in a visualized instance of Ubuntu server (Feisty) that runs with 2 GB RAM and a dedicated dual-core x86_64 processor.

CATALINA_OPTS="-server -Xmx1024 -Xms1024 -XX:+UseParallelGC -XX:+AggressiveOpts"

I don’t have any heuristics on the improvement, but it is a noticeable difference in both speed and processor utilization.

Without attempting to rehash the nitty-gritty of the ergonomics of the JVM, you’re bascially telling Java to act as a server, use a statically sized heap (the memory allocated for object storage), uses young-generation garbage collection (it divides garbage collection across processors), and turning on point release performance optimizations.

For more info on setting up the JVM to be “server-class”, check out the Java Tuning White Paper. While this paper specifically refers to the Java 5 platform, these same options will work if you’ve deployed under Java 6.


Explaining RSS & Serendipity on the Internet

September 22, 2006

RSS is a concept that I have a difficult time describing in a way that doesn’t result in a thought baloon with Huh? appearing over the listener’s head. Stephanie Quilao over at Back In Skinny Jeans does a terrific job with her post, How to explain RSS the Oprah way. In tech-speak, RSS is “Really Simple Syndication.” In Oprah-speak, it is “Ready for some stories.” Read Stephanie’s explanation regardless of your experience. If you know nothing about RSS, the scales will fall from your eyes. If you are a whiz with RSS, it will help you explain it to your colleagues.

When you go to Back in Skinny Jeans you might ask yourself, “What earthly reason does Mack have for going to a web site about beauty and weight loss?” My arrival there is an example of how information is distributed across the Internet and how unlikely connections are made. The sequence went like this:

  1. Stephanie posts the article to her blog
  2. Steve Rubel on the Micro Persuasion blog posts about it later that day.
  3. Jill Stover picks up the story from Micro Persuasion and blogs about it today on her blog, Library Marketing-Thinking Outside the Book. Jill is the Undergraduate Services Librarian at VCU, by the way.
  4. I’m a subscriber to Library Marketing, I read Stephanie’s “how to …”, and wrote this blog entry.

There are three degrees of separation between me and the original blog entry. If I didn’t subscribe to blogs, I might not have run across Stephanie’s blog entry since weight loss and beauty would not ordinarily be interest triggers for me. But because I subscribe to 153 blogs (soon to be 154 after I add Micro Persuasion) this sort of unlikely linkage is less remarkable than you might think. On the Internet you really can’t predict where something of interest will turn up. So read a lot, read broadly, and follow links – there is a lot of good stuff out there.