Re: [Chicken-hackers] Need help to understand C_mutate better.

[Jörg F . Wittenberger]

> From that theory I've been working in trial&error mode again.

I added a (gc) call to the end of my SIGCHLD handler.
Guess what: It did not run into the first, almost-for-sure
case.  Often enough to make me walk the dog waiting for the second
case: the laptop coming back from a longer suspension period.

Now I wonder: as far as I understand C_mutate it will remember
all assignments where the assigned value in within the nursery.

True?

If true, than I don't understand why we allow the mutation_stack
to ever grow beyond the size of the nursery.

So far untested/unimplemented (I'd rather get that understanding
of the mutation stack before I continue here): If we would
check a mutation stack usage limit before the interrupt limit
and at least enforce a minor gc on excess, we might be able to
leave the interrupt handling at the begin of the C_reclaim
and still avoid running havoc.

Reasonable?

/Jörg

> On Oct 21 2011, Jörg F. Wittenberger wrote:
>
> > > The mutation stack will
> > > grow until a garbage collection takes place, so if you
> > > invoke C_mutate in a C loop without giving GC a chance,
> > > the mutations will just add up.
>
> Reading C_reclaim still without fully understanding how
> exactly is will interact with C_context_switch
> it appears to me that if there where always an interrupt
> pending (or at least too often) then chicken would
> dispatch to the interrupt handler, which will switch context.