Re: basic questions on MPS

[Gerd Möllmann]

Helmut Eller <eller.helmut@gmail.com> writes:

> I'd also have some MPS related questions.  Just curiosity.
>
> 1) Does somebody have experience with this MMTK [https://www.mmtk.io/]?
> How does it compare to MPS?

Can't say much, I'm afraid. ISTR that it is relatively young, and they
said somewhere that they are not for production use yet (ca. half a year
ago). That's about what I recall. And it's Rust, if that matters.

> 2) When I learned that MPS uses hardware based read barriers, I was
> surprised.  I had somewhere in the back of my mind some vague
> memory/opinion that those are too slow to be practical.  But I actually
> don't know why that should be the case.  Can somebody explain what the
> problem with hardware based read barriers could be?

I pass.

> 3) MPS uses a mostly-copying strategy.  Copying works well for
> short-lived objects.  For long-lived objects it's not so great.  The big
> guys (OpenJDK, V8 etc.) switch to mark-compact or something else for
> older generations.  Does MPS do something special for long-lived
> objects?

I haven't seen something mentioned in the docs.