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From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Newsgroups: gnu.bash.bug
Subject: Re: [PATCH 5.1] zread: read files in 4k chunks
Date: Mon, 22 Jun 2020 14:17:41 -0600
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On Mon, Jun 22, 2020 at 2:16 PM Ilkka Virta <itvirta@iki.fi> wrote:
>
> On 22.6. 19.35, Chet Ramey wrote:
> > On 6/22/20 1:53 AM, Jason A. Donenfeld wrote:
> >> Currently a static sized buffer is used for reading files. At the moment
> >> it is extremely small, making parsing of large files extremely slow.
> >> Increase this to 4k for improved performance.
> >
> > I bumped it up to 1024 initially for testing.
>
> It always struck me as odd that Bash used such a small read of 128
> bytes. Most of the GNU utils I've looked at on Debian use 8192, and a
> simple test program seems to indicate glibc's stdio reads 4096 bytes at
> one read() call.

Plus most other shells people use...