Profiling

There are many expensive commercial tools for profiling Java programs while they're running, but since Java has the JVMPI interface pretty much anyone can hook into the JVM at run time and find out what's going on. This is another category of programs where there seem to be far too many half-baked efforts, but here are my notes from a few hours of fooling around with various tools.

JTreeProfiler - http://sourceforge.net/projects/jcoverage/ this one streams to an XML file on a per method invocation basis so it's probably unsuitable for anything but trivial profiling (booting JBoss wrote a 2.3GB file). The analysis GUI is interesting and very graphical but hard to make sense of.

JPerfAnal - http://sourceforge.net/projects/jperfanal/ can you think of a more unfortunate name for a performance analysis tool? In any case this guy seems to have the right idea in that he reads the stock Sun profiler output so he doesn't need a platform-specific library to gather data. Unfortunately his GUI is lame and there's not one word of documentation.