"Spawn as many thousand threads as you like" and D

[Russel Winder via Digitalmars-d]

On Wed, 2014-04-16 at 16:06 +0200, Sönke Ludwig via Digitalmars-d wrote:
[…]
> 
> I agree, but I also wonder why you still keep ignoring vibe.d. It 
> achieves exactly that - right now! Integration with std.concurrency 
> would be great, but at least for now it has an API compatible 
> replacement that can be merged later when Sean's pull request is done.

Vibe.d is a single-thread event system, which is great (*) for the sort
of problems Node.js, Vert.x, Tornado, Flask, Sinatra, Ratpack are used
for. The point here is that CSP and dataflow are a concurrency and
parallelism model that D has not got.

std.concurrency is a heavyweight thread system so not really useful
except to build thread pools and fork-join infrastructure. (OK that is a
gross oversimplification.) std.parallelism is a great beginning of data
parallelism on a thread pool. It needs more work. The thread pool needs
to be brought front and centre, as a separate thing usable by other
modules. On this CSP, dataflow, actors, etc. can be built.

Due to other commitments, not least leading a massive update of GPars, I
cannot lead on working on D things. If however someone can drive, I will
certainly contribute, along the lines as I did when David Simcha wrote
std.parallelism – mostly as a tester and reviewer.

This also raises the issue of the D infrastructure having an obvious and
documented way for people to contribute to things like std.parallelism.
Whatever the truth, the perception is that to work on something like
std.parallelism, you have to fork the whole of Phobos. In fact,
std.parallelism is a single file 4,500 lines long (**).


(*) It would be even better if it supported mocking for unit tests ;-)

(**) I am still not a fan of single files this big.
-- 
Russel.
=============================================================================
Dr Russel Winder      t: +44 20 7585 2200   voip: sip:russel.winder at ekiga.net
41 Buckmaster Road    m: +44 7770 465 077   xmpp: russel at winder.org.uk
London SW11 1EN, UK   w: www.russel.org.uk  skype: russel_winder