Ovidiu Dimulescu provides tips for working with local and remote JVMs, startup flags, analyzing and correlating thread dumps with CPU consumption, instrumentation, multi-tenant JVMs, memory games, etc
Sadek Drobi discusses how to use Futures and Iteratees to deal with blocking threads in a system with many IO calls and heavy threads.
Tom Enebo explains reasons for choosing JRuby: Hotspot optimizations, JVM Garbage Collectors, tools like profilers. Also: how JRuby helps to write cleaner, more expressive code with Java libraries.
Brian Goetz discusses the difficulties of creating multithreaded programs correctly, incorrect synchronization, race conditions, deadlock, STM, concurrency, alternatives to threads, Erlang, Scala.