Dawn of the Dead Ends: Fixing a Memory Leak in Apache Kafka

At Heroku, we're always working towards increased operational stability with the services we offer. As we recently launched the beta of Apache Kafka on Heroku, we've been running a number of clusters on behalf of our beta customers.

Over the course of the beta, we have thoroughly exercised Kafka through a wide range of cases, which is an important part of bringing a fast-moving open-source project to market as a managed service. This breadth of exposure led us to the discovery of a memory leak in Kafka, having a bit of an adventure debugging it, and then contributing a patch to the Apache Kafka community to fix it.

Issue Discovery

For the most part, we’ve seen very few issues...

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Run JRuby on Heroku Right Now


Over a year ago Heroku launched the Cedar stack and the ability to run Java on our platform. Java is known as a powerful language - capable of performing at large scale. Much of this potential comes from the JVM that Java runs on. The JVM is the stable, optimized, cross-platform virtual machine that also powers other languages including Scala and Clojure. Starting today you can leverage the power of the JVM in your Ruby applications without learning a new language, by using JRuby on Heroku.

After a beta process with several large production applications, we are pleased to move JRuby support into general availability immediately. One of these companies Travis CI which provides free CI...

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