[jmreardon]

I can tell you is isn't being deallocated before being used, that would be a major bug. So, I guess it would get moved, but the GC probably won't run unless the first gen space is pretty full. I'm glossing over details because, well, the GC in the JVM is a very complicated piece of work, and I don't know much of the details, but the JVM does in fact default to a stop-the-world garbage collector[1].

I don't think anyone actually expects the JVM to beat C++ using stack allocated objects[2]. Our concern is how well a garbage collector handles lots of small objects.

[1] Details on how the JVM GC works: http://www.oracle.com/technetwork/java/gc-tuning-5-138395.ht... [2] There is a switch, which will be on by default one day, that lets the JVM do escape analysis so it can allocate objects on the stack automatically.