Moving towards Python 3.0 (was Re: [Python-Dev] Speed up function calls)

[Evan Jones]

On Jan 31, 2005, at 0:17, Guido van Rossum wrote:
> The "just kidding" applies to the whole list, right? None of these
> strike me as good ideas, except for improvements to function argument
> passing.

Really? You see no advantage to moving to garbage collection, nor 
allowing Python to leverage multiple processor environments? I'd be 
curious to hear your reasons why not.

My knowledge about garbage collection is weak, but I have read a little 
bit of Hans Boehm's work on garbage collection. For example, his 
"Memory Allocation Myths and Half Truths" presentation 
(http://www.hpl.hp.com/personal/Hans_Boehm/gc/myths.ps) is quite 
interesting. On page 25 he examines reference counting. The biggest 
disadvantage mentioned is that simple pointer assignments end up 
becoming "increment ref count" operations as well, which can "involve 
at least 4 potential memory references." The next page has a 
micro-benchmark that shows reference counting performing very poorly. 
Not to mention that Python has a garbage collector *anyway,* so 
wouldn't it make sense to get rid of the reference counting?

My only argument for making Python capable of leveraging multiple 
processor environments is that multithreading seems to be where the big 
performance increases will be in the next few years. I am currently 
using Python for some relatively large simulations, so performance is 
important to me.

Evan Jones