parsort.1

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.\" ========================================================================
.\"
.IX Title "PARSORT 1"
.TH PARSORT 1 "2021-03-22" "20210322" "parallel"
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
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.nh
.SH "NAME"
parsort \- Sort (big files) in parallel
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
\&\fBparsort\fR \fIoptions for sort\fR
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
\&\fBparsort\fR uses \s-1GNU\s0 \fBsort\fR to sort in parallel. It works just like
\&\fBsort\fR but faster on inputs with more than 1 M lines, if you have a
multicore machine.
.PP
Hopefully these ideas will make it into \s-1GNU\s0 \fBsort\fR in the future.
.SH "EXAMPLE"
.IX Header "EXAMPLE"
Sort files:
.PP
.Vb 1
\&  parsort *.txt > sorted.txt
.Ve
.PP
Sort stdin (standard input) numerically:
.PP
.Vb 1
\&  cat numbers | parsort \-n > sorted.txt
.Ve
.SH "PERFORMANCE"
.IX Header "PERFORMANCE"
\&\fBparsort\fR is faster on files, because these can be read in parallel.
.PP
On a 48 core machine you should see a speedup of 3x over \fBsort\fR.
.SH "AUTHOR"
.IX Header "AUTHOR"
Copyright (C) 2020\-2021 Ole Tange,
http://ole.tange.dk and Free Software Foundation, Inc.
.SH "LICENSE"
.IX Header "LICENSE"
Copyright (C) 2012 Free Software Foundation, Inc.
.PP
This program is free software; you can redistribute it and/or modify
it under the terms of the \s-1GNU\s0 General Public License as published by
the Free Software Foundation; either version 3 of the License, or
at your option any later version.
.PP
This program is distributed in the hope that it will be useful,
but \s-1WITHOUT ANY WARRANTY\s0; without even the implied warranty of
\&\s-1MERCHANTABILITY\s0 or \s-1FITNESS FOR A PARTICULAR PURPOSE.\s0  See the
\&\s-1GNU\s0 General Public License for more details.
.PP
You should have received a copy of the \s-1GNU\s0 General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
.SH "DEPENDENCIES"
.IX Header "DEPENDENCIES"
\&\fBparsort\fR uses \fBsort\fR, \fBbash\fR, and \fBparallel\fR.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
\&\fBsort\fR