[Vm-dev] Cogmt

[Frank Shearar]

So we have builds running all in-image tests, and the test suites of a
bunch of packages, and running these on the latest stable Interpreter
VM, and the latest Cog VM.

We _don't_ yet run tests on the cogmt VM, mainly because I'm lazy and
I don't know anything about cogmt beyond supposing that "mt" means
"multithreaded". Should we? Is there a place where I can read up on
cogmt?

frank