Is there a JVM aimed at debugging concurrent software?

I've used 开发者_如何学编程Concurrent Pascal, a tool which helps debug concurrent algorithms because when it runs your code, it randomizes which thread to swap to at every possible step, trying out as many paths as possible.

Is there a JVM that can do this?

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Take a look at the Java Pathfinder (from NASA, nonetheless—and it's free). I think it should do what you need almost out of the box, that is, trying different interleavings (some assembly may be required).

Of course, you still need to specify the verification property on your data that you're interested in, like an invariant. Otherwise, by default it would probably only tell you if there was a deadlock. Take a look at the section "Explore Execution Alternatives".

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There are no commercial JVMs I'm aware of that do this, but I suggest you look at tools like ConTest that try to help you in your problem domain:

ConTest on developerWorks

ConTest on research site

In general, because most commerical JVMs rely on the OS to do thread scheduling, it's not a natural thing for JVMs themselves to do. There might be something out there for the green-threads versions of Jikes-RVM (which might be the older ones).