From: "Pádraig Brady" <P@draigBrady.com>
To: "DE CARNE DE CARNAVALET,
Xavier [COMP]" <xavier.decarnedecarnavalet@polyu.edu.hk>,
60544@debbugs.gnu.org
Subject: bug#60544: sort hangs on lengthy line with invalid UTF8 characters
Date: Sun, 8 Jan 2023 22:03:28 +0000 [thread overview]
Message-ID: <f5db42ee-1b83-b71a-47cc-101a7bb87ea8@draigBrady.com> (raw)
In-Reply-To: <TYYP286MB3044FCE22F8A297AE174FA4BA3F59@TYYP286MB3044.JPNP286.PROD.OUTLOOK.COM>
tag 60544 notabug
close 60544
stop
On 04/01/2023 04:38, DE CARNE DE CARNAVALET, Xavier [COMP] wrote:
> sort seems to do extra computations on long line with invalid UTF8 characters and could hang for days on just two lines.
>
> Here is the minimal example I could make to reproduce the bug:
> $ perl -e 'print "\xcd\xe5\xe0"; print "\n"' > file1
> $ perl -e 'print "\xcd\xe5\xe0"x1000; print "\n"' > file2
> Then:
> $ export LC_ALL=en_US.UTF8
> $ time sort --debug file1 file2
> sort: using 'en_US.UTF8' sorting rules
> [...]
> real 0m1.951s
> user 0m1.951s
> sys 0m0.000s
>
> It took nearly two seconds to sort two lines from two files.
> If I replace the \xe0 with \x61 in the first (small) file, the time gets down to milliseconds:
If I profile sort like:
$ src/sort file1 file2 >/dev/null & perf top -p $!
It shows that all the time is spent in libc's __strcoll_l
I see one strcoll performance bug which might be related:
https://sourceware.org/bugzilla/show_bug.cgi?id=18441
I'd follow up with glibc, also specifying your glibc version.
Marking this as not a coreutils bug for now.
cheers,
Pádraig
prev parent reply other threads:[~2023-01-08 22:04 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-01-04 4:38 bug#60544: sort hangs on lengthy line with invalid UTF8 characters DE CARNE DE CARNAVALET, Xavier [COMP]
2023-01-08 22:03 ` Pádraig Brady [this message]
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