[Python-Dev] PEP 575 (Unifying function/method classes) update

Nick Coghlan ncoghlan at gmail.com
Wed Jun 20 07:43:20 EDT 2018

On 19 June 2018 at 16:12, INADA Naoki <songofacandy at gmail.com> wrote:
> On Tue, Jun 19, 2018 at 2:56 PM Jeroen Demeyer <J.Demeyer at ugent.be> wrote:
>> On 2018-06-18 16:55, INADA Naoki wrote:
>> > Speeding up most python function and some bultin functions was very
>> > significant.
>> > But I doubt making some 3rd party call 20% faster can make real
>> > applications significant faster.
>> These two sentences are almost contradictory. I find it strange to claim
>> that a given optimization was "very significant" in specific cases while
>> saying that the same optimization won't matter in other cases.
> It's not contradictory because there is basis:
>   In most real world Python application, number of calling Python methods or
>   bulitin functions are much more than other calls.
> For example, optimization for bulitin `tp_init` or `tp_new` by FASTCALL was
> rejected because it's implementation is complex and it's performance gain is
> not significant enough on macro benchmarks.
> And I doubt number of 3rd party calls are much more than calling builtin
> tp_init or tp_new.

I was going to ask a question here about JSON parsing
micro-benchmarks, but then I went back and re-read
and realised that the main problem discussed in that article was the
*memory* overhead of creating full Python object instances, not the
runtime cost of instantiating those objects.


Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia

More information about the Python-Dev mailing list