How parallel are parallel tests in Ruby 1.9.3?

Question

In Ruby 1.9.3, you're allowed to run multiple test cases at once. I'm not sure whether this is a feature of the language, the minitest library, or a feature of YARV, so apologies for any bad terminology.

But have they eliminated the GVL for this, or does this merely mean that if one thread's doing IO, another thread can utilize the CPU?

Answer 1

The implementation doesn't use threads, but separate processes communicating through pipes. See e.g. this presentation. So the GVL/GIL doesn't come into play.