NAME
    Bencher::Scenario::SortingByKey - Benchmark various techniques to sort
    array by some computed key

VERSION
    This document describes version 0.001 of Bencher::Scenario::SortingByKey
    (from Perl distribution Bencher-Scenario-SortingByKey), released on
    2019-12-25.

SYNOPSIS
    To run benchmark with default option:

     % bencher -m SortingByKey

    To run module startup overhead benchmark:

     % bencher --module-startup -m SortingByKey

    For more options (dump scenario, list/include/exclude/add participants,
    list/include/exclude/add datasets, etc), see bencher or run "bencher
    --help".

DESCRIPTION
    Packaging a benchmark script as a Bencher scenario makes it convenient
    to include/exclude/add participants/datasets (either via CLI or Perl
    code), send the result to a central repository, among others . See
    Bencher and bencher (CLI) for more details.

BENCHMARKED MODULES
    Version numbers shown below are the versions used when running the
    sample benchmark.

    Sort::Key 1.33

BENCHMARK PARTICIPANTS
    *   uncached (perl_code)

        Code template:

         state $array=<array>; sort { -$a <=> -$b } @$array

    *   ST (perl_code)

        Code template:

         state $array=<array>; map { $_->[0] } sort { $a->[1] <=> $b->[1] } map { [$_, -$_] } @$array

    *   GRT (perl_code)

        Code template:

         state $array=<array>; map { $_->[0] } sort { $a->[1] <=> $b->[1] } map { [$_, -$_] } @$array

    *   2array (perl_code)

        Code template:

         state $array=<array>; my @keys = map { -$_ } @$array; my @indexes = 0..$#{$array}; map { $array->[$_] } sort { $keys[$a] <=> $keys[$b] } @indexes

    *   Sort::Key::nkeysort (perl_code)

        Code template:

         state $array=<array>; Sort::Key::nkeysort(sub { -$_ }, @$array)

BENCHMARK DATASETS
    *   10

    *   100

    *   1000

    *   10000

SAMPLE BENCHMARK RESULTS
    Run on: perl: *v5.30.0*, CPU: *Intel(R) Core(TM) i5-7200U CPU @ 2.50GHz
    (2 cores)*, OS: *GNU/Linux Ubuntu version 19.04*, OS kernel: *Linux
    version 5.0.0-37-generic*.

    Benchmark with default options ("bencher -m SortingByKey"):

     #table1#
     +---------------------+---------+-----------+------------+------------+---------+---------+
     | participant         | dataset | rate (/s) | time (ms)  | vs_slowest |  errors | samples |
     +---------------------+---------+-----------+------------+------------+---------+---------+
     | ST                  | 10000   |        63 | 16         |      1     | 4.6e-05 |      21 |
     | GRT                 | 10000   |        63 | 16         |      1     |   5e-05 |      20 |
     | 2array              | 10000   |       110 |  9.1       |      1.7   | 1.5e-05 |      20 |
     | Sort::Key::nkeysort | 10000   |       326 |  3.07      |      5.19  | 2.9e-06 |      20 |
     | GRT                 | 1000    |       867 |  1.15      |     13.8   | 6.9e-07 |      20 |
     | ST                  | 1000    |       888 |  1.13      |     14.1   | 6.9e-07 |      20 |
     | 2array              | 1000    |      1560 |  0.64      |     24.8   | 2.7e-07 |      20 |
     | Sort::Key::nkeysort | 1000    |      3820 |  0.262     |     60.8   | 2.1e-07 |      20 |
     | ST                  | 100     |     12533 |  0.0797893 |    199.268 | 6.4e-11 |      20 |
     | GRT                 | 100     |     13000 |  0.079     |    200     | 1.1e-07 |      20 |
     | 2array              | 100     |     21800 |  0.0459    |    346     | 1.3e-08 |      21 |
     | Sort::Key::nkeysort | 100     |     51420 |  0.01945   |    817.5   | 2.2e-10 |      20 |
     | uncached            | 10000   |    150000 |  0.00667   |   2380     | 3.1e-09 |      23 |
     | ST                  | 10      |    200000 |  0.005     |   3180     | 1.7e-09 |      20 |
     | GRT                 | 10      |    201000 |  0.00497   |   3200     | 1.6e-09 |      22 |
     | 2array              | 10      |    318710 |  0.0031376 |   5067.4   | 2.3e-11 |      23 |
     | Sort::Key::nkeysort | 10      |    505400 |  0.001979  |   8035     | 1.5e-10 |      20 |
     | uncached            | 1000    |   1464000 |  0.0006831 |  23270     | 3.7e-11 |      20 |
     | uncached            | 100     |   9900000 |  0.0001    | 160000     | 2.1e-10 |      20 |
     | uncached            | 10      |  25000000 |  0.00004   | 390000     | 7.5e-11 |      20 |
     +---------------------+---------+-----------+------------+------------+---------+---------+

    Benchmark module startup overhead ("bencher -m SortingByKey
    --module-startup"):

     #table2#
     +---------------------+-----------+------------------------+------------+---------+---------+
     | participant         | time (ms) | mod_overhead_time (ms) | vs_slowest |  errors | samples |
     +---------------------+-----------+------------------------+------------+---------+---------+
     | Sort::Key           |      14   |                    7.1 |          1 | 1.7e-05 |      20 |
     | perl -e1 (baseline) |       6.9 |                    0   |          2 | 1.9e-05 |      20 |
     +---------------------+-----------+------------------------+------------+---------+---------+

    To display as an interactive HTML table on a browser, you can add option
    "--format html+datatables".

HOMEPAGE
    Please visit the project's homepage at
    <https://metacpan.org/release/Bencher-Scenario-SortingByKey>.

SOURCE
    Source repository is at
    <https://github.com/perlancar/perl-Bencher-Scenario-SortingByKey>.

BUGS
    Please report any bugs or feature requests on the bugtracker website
    <https://rt.cpan.org/Public/Dist/Display.html?Name=Bencher-Scenario-Sort
    ingByKey>

    When submitting a bug or request, please include a test-file or a patch
    to an existing test-file that illustrates the bug or desired feature.

SEE ALSO
    Guttman, U., & Rosler, L. (2003). A fresh look at efficient perl
    sorting. <http://www.sysarch.com/Perl/sort_paper.html>. This is the
    original paper that mentions GRT.

    <https://www.perlmonks.org/?node_id=145659>

    <https://www.perlmonks.org/?node_id=287149>

    Sort::Maker, also by Uri Guttman, describes the various sort techniques
    (ST, GRT, etc).

    Sort::Key by Salvador Fandiño García.

AUTHOR
    perlancar <perlancar@cpan.org>

COPYRIGHT AND LICENSE
    This software is copyright (c) 2019 by perlancar@cpan.org.

    This is free software; you can redistribute it and/or modify it under
    the same terms as the Perl 5 programming language system itself.