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From: Lawrence D'Oliveiro <ldo@nz.invalid>
Newsgroups: comp.lang.python
Subject: Re: GIL-Removal Project Takes Another Step (Posting On Python-List
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Date: Wed, 20 Mar 2024 03:14:49 -0000 (UTC)
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On Tue, 19 Mar 2024 17:51:54 -0700, Paul Rubin wrote:

> Lawrence D'Oliveiro <ldo@nz.invalid> writes:
>
>> So even a very simple, seemingly well-behaved Python script, if running
>> for long enough, would consume more and more memory if it were not for
>> reference-counting.
> 
> That is completely false.  It's usual to set a GC to [fix it so it’s not
> false] ...

In other words, it’s not “completely” false if you have to do something to 
make it false. But that GC process creates its own overhead, not to 
mention the latency when there isn’t quite enough memory for an allocation 
and you have to wait until the next GC run to proceed. Run the GC a 
thousand times a second, and the latency is still 1 millisecond.

With reference counting, most objects are immediately freed as soon as 
they are discarded--no need to wait for the next GC run.