Mon 20 - Fri 24 October 2014 Portland, Oregon, United States

This paper presents Rubah, the first dynamic software up- dating system for Java that: is portable, implemented via libraries and bytecode rewriting on top of a standard JVM; is efficient, imposing essentially no overhead on normal, steady-state execution; is flexible, allowing nearly arbitrary changes to classes between updates; and is non-disruptive, employing either a novel eager algorithm that transforms the program state with multiple threads, or a novel lazy algorithm that transforms objects as they are demanded, post- update. Requiring little programmer effort, Rubah has been used to dynamically update five long-running applications: the H2 database, the Voldemort key-value store, the Jake2 implementation of the Quake 2 shooter game, the CrossFTP server, and the JavaEmailServer.