on Jun 20th, 2009Memory Analyser, Eclipse Galileo Feature #5
With all the great work going on in the Eclipse Run-time space, like the EMF Runtime, RAP, Birt Charting Engine, ECF, Jetty and of course Equinox, I sometimes forget that Eclipse started as an excellent platform for tools. The Eclipse Memory Analyzer project reminded me just how good Eclipse tools are.
All week I have been counting down the top 10 Galileo features that I’m most excited about. Number 5 on my list is the Eclipse Memory Analyzer (MAT). This project was first released in December 2008 and is now part of the Galileo release train. MAT provides a large selection of features to help you analyze Java heap dumps to understand your memory consumption and help remove leaks.
As you may have noticed, many of my posts focus on the simplicity of the new features. The MAT project is no different. Getting started with the Memory Analyzer is a simple 3 step process:
- Install the MAT tools (optionally install the charting engine too). (Hint: Use p2 for this)
- Grab a heap dump:I simply used the JMap tool available with my JDK. 12345 was the PID of my Eclipse process.
$ jmap -heap:format=b 12345 - Open the Heap Dump
JMap generates a file called heap.bin
Some of the notable features include:
Shout-outs for this go to Andreas Buchen and the entire Memory Analyzer team. Thank-you for guys for such an awesome (and unbelievably useful) tool!
Note: I got these examples by running the memory analyzer on Eclipse, after analyzing a 670 Meg heap. It’s unbelievable, but the MAT heap was only 21 Megs. 21 Megs used to analyze over 1/2 a Gig. How cool is that?
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I had a pleasure to work with MAT when we had memory problems with our server in my day job. It is a fantastic tool! It builds own indexes about objects in the heap, and is very fast doing various queries. As you point out, doesn’t consume lot of memory. Its leak suspects quickly revealed where the problem is (in our case, jdbc driver was the culprit), and using thread view we quickly found out what happened. I am looking forward to using it again … although I hope that I will not need to
Ian,
Thanks man for this great series. I wish you would have started at 20.