Re: [Caml-list] Multicore runtime

[Roberto Di Cosmo <roberto@dicosmo.org>]

I believe a lot of code written using lightweight threads takes
advantage of the fact that only one "thread" at a time has access to
the state, as this provides us with the huge plus of writing code that
does not need locks to prevent data races. In other words, while there
is the illusion of having concurrent code running, we only have a big
sequential piece of code under execution, and we rely on this fact.

To take advantage of multicore, it would be IMHO very dangerous to
change the behaviour of lwt/async to allow real concurrent execution,
so the need of a separate mechanisms is real, and the proposed
approach using domains and fibers seems quite sensible to me, even if
others are possible (and various has been tried already).

I am more worried about the unexpected behaviours that will arise once
one starts to write code mixing these new abstractions with code using
lightweight threads: time will tell :-)


2014-09-08 12:27 GMT+02:00 Peter Zotov <whitequark@whitequark.org>:
> On 2014-09-08 14:05, Stephen Dolan wrote:
>>
>> On Sun, Sep 7, 2014 at 10:47 PM, Jiten Pathy <jpathy@fssrv.net> wrote:
>>>
>>> Hello,
>>> Nice work by stephen et al. on multicore runtime. Just had some
>>> questions:-
>
>
> I have some questions as well.
>
> Most importantly, why are there fibers at all? We already have Async/Lwt
> fragmentation. Would fibers add a third option?
>
> Would it not be enough to teach the GC how to interact with multiple
> threads/domains?
>
> --
> Peter Zotov
>
>
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-- 
Roberto Di Cosmo

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