discussion: serialize procedures and continuations

discussion: serialize procedures and continuations

[Chaos Eternal]

In Scheme, procedures are closures, that means it has the code of the
procedure itself as well as the required environment for running that
procedure. And, mostly, continuations are considered closure.

Hence, it is reasonable to expect a way to serialize the closures to
disks and/or remote machines over network.

Usage:
Stored procedures can be restored later or restored remotely which
makes remote procedure call more easier.
Problems are when these procedures contain reference to object outside
the scheme, say, opened fds, acquired locks/mutexes these objects will
lost. But hooks can be added to overcome these problems.

Stored continuations can restored later to make program continue to
running after system failure, or, in web application, can be used to
finish a user transaction. also, stored continuations can be
transferred to remote hosts to make process-migration. still hooks are
needed when programmer need to deal with opened files and so on.

existing implementations:
Gambit-C: the termite module of gambit-c heavily depends on
serializable closures to have functions like remote process call,
process migration and remote spawn.
chicken: chicken has termite port and also has these function implemented.

I am porting termite to guile. that's why I am interesting in this.

Re: discussion: serialize procedures and continuations

[Ludovic Courtès]

Chaos Eternal <chaoseternal@shlug.org> skribis:

> existing implementations:
> Gambit-C: the termite module of gambit-c heavily depends on
> serializable closures to have functions like remote process call,
> process migration and remote spawn.
> chicken: chicken has termite port and also has these function implemented.

In Guile 2.0, you may be able to do implement closure serialization with
support from (system vm program).

(That will not be portable to 2.1/2.2, though.)

> I am porting termite to guile. that's why I am interesting in this.

Nice.

HTH,
Ludo’.

Re: discussion: serialize procedures and continuations

[Andy Wingo]

On Thu 15 Aug 2013 15:47, Chaos Eternal <chaoseternal@shlug.org> writes:

> Hence, it is reasonable to expect a way to serialize the closures to
> disks and/or remote machines over network.

Agreed.  Guile 2.2's compiler might be able to do this, with some
modification -- take a closure and tree-shake out its dependencies,
packaged into an ELF image.  Similar to save-lisp-and-die in some ways.
But that's a bit expensive to do; there should probably be a way of
doing it at compile-time instead of at run-time.

Andy
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