From: Sebastian Gniazdowski <sgniazdowski@gmail.com>
To: Roman Perepelitsa <roman.perepelitsa@gmail.com>
Cc: Zsh hackers list <zsh-workers@zsh.org>
Subject: Re: accessing array by index very slow
Date: Sun, 16 Apr 2023 11:19:49 +0200 [thread overview]
Message-ID: <CAKc7PVAgXMCoFKgVu4Wy=43C=NpC3zECPLirX9O9y1m7QCAY4A@mail.gmail.com> (raw)
In-Reply-To: <CAN=4vMouxgQNP=sfrXDhvtUkgLZgkDd6Z3GZX04rHGOhDwihpg@mail.gmail.com>
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There was badarrays branch from Mikachu in the past. it was resolving
constant arrlen() calling.
niedz., 16 kwi 2023, 11:10 użytkownik Roman Perepelitsa <
roman.perepelitsa@gmail.com> napisał:
> On Sun, Apr 16, 2023 at 11:04 AM Stephane Chazelas
> <stephane@chazelas.org> wrote:
> >
> > Accessing array elements via their index is very slow,
> > especially for large index values.
>
> Indeed, access to array elements is O(N) in zsh instead of O(1) that
> one might expect. The same goes for strings, even with no_multibyte.
> This makes computation-heavy code incredibly slow. If someone can fix
> this, they'll have my eternal gratitude.
>
> On the plus side zsh has fast hashtables (closed hashing with
> quadratic probing). Bash's implementation is a lot slower (it's
> node-based).
>
> Roman.
>
>
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next prev parent reply other threads:[~2023-04-16 9:20 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-04-16 9:03 Stephane Chazelas
2023-04-16 9:10 ` Roman Perepelitsa
2023-04-16 9:19 ` Sebastian Gniazdowski [this message]
2023-04-16 15:27 ` Bart Schaefer
2023-04-16 22:03 ` Mikael Magnusson
2023-04-18 2:43 ` Bart Schaefer
2023-04-30 19:26 ` Bart Schaefer
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