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From: Sebastian Gniazdowski <sgniazdowski@gmail.com>
To: Zsh Users <zsh-users@zsh.org>
Subject: Fastest way to count # of files?
Date: Thu, 8 Sep 2016 17:36:35 +0200	[thread overview]
Message-ID: <CAKc7PVApZGBAoQ4GywTLzbJXmNOrq2-W_iP7p+ifWqzYF49N+g@mail.gmail.com> (raw)

Hello,
I'm trying to protect from slow NFS hierarchies and large directory
tries. This is fast:

% typeset -F SECONDS; myst=$SECONDS; arr=( *rarestring(NY1) ); echo
$(( (SECONDS - myst) * 1000 ))
80.286000000342028


this is slow:

% typeset -F SECONDS; myst=$SECONDS; arr=( * ); echo ${#arr}; echo $((
(SECONDS - myst) * 1000 ))
1154.1240000005928


First code obviously has to read every file in directory. But it's
doing this fast. The second code reads the whole directory too, but
it's slow. First code doesn't provide way to determine # of files
read. Is there anything between these two? Something that doesn't
store files, but counts them?

Best regards,
Sebastian Gniazdowski


             reply	other threads:[~2016-09-08 15:42 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-09-08 15:36 Sebastian Gniazdowski [this message]
2016-09-08 16:08 ` Bart Schaefer
2016-09-08 16:37   ` Sebastian Gniazdowski
2016-09-08 20:00     ` Bart Schaefer
2016-09-09  1:09       ` Bart Schaefer
     [not found]       ` <160908180958.ZM14692__14483.1264777624$1473385001$gmane$org@torch.brasslantern.com>
2016-09-09  5:36         ` Daniel Shahaf
2016-09-09 16:31           ` Bart Schaefer

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