Are your GC logs speaking to you?

by Kirk Pepperdine 

Thursday, 14 June 2012 16:40

If you wanna know what your garbage collector is up to the best place to look is in the GC logs. That said, the GC logs are like any other ascii log file in that they can be full of 1000s of cryptic entries which make trying to figure out what the logs are saying without any tooling, a daunting task. In this session I will introduce Censum, a free tool designed to help you make sense out of your log files. Some of what Censum can tell you is if your JVM’s heap is misconfigured. For example, a large number of applications currently running in products systems are starved for memory in at least one of their internal memory pools. But it’s not only starvation that can a cause of poor performance or long GC pauses. Too much memory can be equally as problematic. Or your problem could be as simple as your application calling System.gc(). WIth Censum sort out what your GC logs are telling you so that you can go on to solve your Java heap rooted performance problems.