Chris Houser discusses stack traces in Clojure and introduces a library for investigating activity across multiple threads and servers, plus a technique for reproducing race conditions.
One tough problem in debugging distributed applications is understanding what happened on a client that later caused an exception on a server. I'll discuss the nature of Clojure stack traces and demonstrate a library that can extend a stack trace from where it was thrown, back across multiple thread or server boundaries to the client that initiated it. Even with more helpful stack traces, however, testing for the handling of race conditions is still very challenging. I'll demonstrate a technique that we've used at LonoCloud in our test suite to consistently reproduce and guard against race conditions.
16th–17th March 2012