[Python-ideas] Optimistic Concurrency

[Dillon Collins]

On Monday 20 October 2008, Adam Olsen wrote:
> Stepping back a bit, there's two distinct problems to solve:
> 1) Making threading easier
> 2) Removing the GIL

As I've not seen it mentioned in this thread, I feel that it's worth pointing 
out that 2.6's new multiprocessing module allows for programs to use more 
than one CPU, thus eventually eliminating the GIL:
http://docs.python.org/dev/2.6/library/multiprocessing.html

In light of this I doubt we'll see the GIL removed from CPython pretty much 
ever.  The GIL does have the benefit of speeding up CPython fairly 
significantly by removing lock overhead, and simplifies the code.  It can 
also be released by C libs for things that will take a long time (which are 
often best in C for that reason anyway).

So, while removing the GIL is fun from an intellectual perspective, it's 
practical value is now somewhat limited.  Sure, multiprocessing isn't 
perfect, but it is the first thing to bypass the GIL that's been accepted ;).