Re: why should physmem not know about which frames are extra?

[Marcus Brinkmann]

At Wed, 27 Oct 2004 12:51:39 +0100,
Sam Mason <address@hidden> wrote:
> 
> Marcus Brinkmann wrote:
> >I have considered this case before writing my mail, and thought that
> >you theoretically could mark the particular frame as guaranteed (from
> >extra) when mapping it write-only (ie, you have to contact physmem
> >anyway).
> 
> Just thinking aloud here. . .  But wouldn't this be a nightmare for a
> program using garbage collection?  Writing a copying collector that
> would keep physmem in sync with its progress wouldn't be my idea
> of fun!

Good point.  Now you know how much I know about garbage collectors.

> If the progress could be maintained "lazily" by physmem
> asking for the information only when it's needed would be a lot
> nicer - in my opinion anyway!

Well, the lazy approach is what Neal suggests and which is so far the
accepted solution, even by me, and even given the obvious problems
arising from it.

Thanks,
Marcus