Asynchronicity in D

[Sean Kelly]

On Mar 31, 2011, at 11:48 AM, dsimcha wrote:

> == Quote from Andrej Mitrovic (andrej.mitrovich at gmail.com)'s article
>> Are fibers really better/faster than threads? I've heard rumors that
>> they perform exactly the same, and that there's no benefit of using
>> fibers over threads. Is that true?
> 
> Here are some key differences between fibers (as currently implemented in
> core.thread; I have no idea how this applies to the general case in other
> languages) and threads:
> 
> 1.  Fibers can't be used to implement parallelism.  If you have N > 1 fibers
> running on one hardware thread, your code will only use a single core.

It bears mentioning that this has interesting implications for the default thread-local storage of statics.  All fibers running on a thread will currently share the thread's static data.  This could be worked around by doing TLS manually at the fiber level, but it's a non-trivial change.