NAME
    Acme::CPANModules::UUID - List of modules that can generate immutable
    universally unique identifier (UUIDs)

VERSION
    This document describes version 0.011 of Acme::CPANModules::UUID (from
    Perl distribution Acme-CPANModules-UUID), released on 2023-10-30.

SYNOPSIS
    To run benchmark with default option:

     % bencher --cpanmodules-module UUID

    To run module startup overhead benchmark:

     % bencher --module-startup --cpanmodules-module UUID

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

DESCRIPTION
    UUIDs (Universally Unique Identifiers), sometimes also called GUIDs
    (Globally Unique Identifiers), are 128-bit numbers that can be used as
    permanent IDs or keys in databases. There are several standards that
    specify UUID, one of which is RFC 4122 (2005), which we will follow in
    this document.

    UUIDs are canonically represented as 32 hexadecimal digits in the form
    of:

     xxxxxxxx-xxxx-Mxxx-Nxxx-xxxxxxxxxxxx

    There are several variants of UUID. The variant information is encoded
    using 1-3 bits in the "N" position. RFC 4122 defines 4 variants (0 to
    3), two of which (0 and 3) are for legacy UUIDs, so that leaves variants
    1 and 2 as the current specification.

    There are 5 "versions" of UUID for both variants 1 & 2, each might be
    more suitable than others in specific cases. The version information is
    encoded in the M position. Version 1 (v1) UUIDs are generated from a
    time and a node ID (usually the MAC address); version 2 (v2) UUIDs from
    an identifier (group/user ID), a time, and a node ID; version 4 (v4)
    UUIDs from a rando/mpseudo-random number; version 3 (v3) UUIDs from
    hashing a namespace using MD5; version 5 (v5) from hashing a namespace
    using SHA-1.

    Data::UUID should be your first choice, and when you cannot install XS
    modules you can use UUID::Tiny instead.

    Aside from the modules listed as entries below, there are also:
    App::UUIDUtils (containing CLIs to create/check UUID), Data::GUID
    (currently just a wrapper for Data::UUID).

ACME::CPANMODULES ENTRIES
    Data::UUID
        Author: RJBS <https://metacpan.org/author/RJBS>

        This module creates v1 and v2 UUIDs. Depending on the OS, for MAC
        address, it usually uses a hash of hostname instead. This module is
        XS, so performance is good. If you cannot use an XS module, try
        UUID::Tiny instead.

        The benchmark code creates 1000+1 v1 string UUIDs.

    UUID::FFI
        Author: PLICEASE <https://metacpan.org/author/PLICEASE>

        This module provides access to libuuid via the FFI interface. It can
        create v1 as well as v4 (random) UUIDs. Note that Data::UUID
        (XS-based) is faster this module (FFI-based).

        The benchmark code creates 1000+1 v1 string UUIDs.

    UUID::Tiny
        Author: CAUGUSTIN <https://metacpan.org/author/CAUGUSTIN>

        This module should be your go-to choice if you cannot use an XS
        module. It can create v1, v3, v4 UUIDs. However, the random v4 UUIDs
        are not cryptographically secure; if you need cryptographically
        secure random UUIDs, use Crypt::Misc.

        The benchmark code creates 1000+1 v1 string UUIDs.

        See also: Types::UUID which is a type library that uses Data::UUID
        as the backend.

    UUID::Random
        Author: PERLER <https://metacpan.org/author/PERLER>

        This module simply uses 32 calls to Perl's rand() to construct each
        random hexadecimal digits of the UUID (v4). Not really recommended,
        since perl's default pseudo-random generator is neither
        cryptographically secure nor has 128 bit of entropy. It also does
        not produce v4 UUIDs that conform to RFC 4122 (no encoding of
        variant & version information).

        To create a cryptographically secure random UUIDs, use Crypt::Misc.

        The benchmark code creates 1000+1 v4 string UUIDs.

    UUID::Random::PERLANCAR
        Author: PERLANCAR <https://metacpan.org/author/PERLANCAR>

        Just another implementation of UUID::Random.

        The benchmark code creates 1000+1 v4 string UUIDs.

    UUID::Random::Secure
        Author: PERLANCAR <https://metacpan.org/author/PERLANCAR>

        Just like UUID::Random, except it uses Math::Random::Secure's
        irand() to produce random numbers.

        The benchmark code creates 1000+1 v4 string UUIDs.

    Crypt::Misc
        Author: MIK <https://metacpan.org/author/MIK>

        This module from the CryptX distribution has a function to create
        and check v4 UUIDs.

        The benchmark code creates 1000+1 v4 string UUIDs.

    UUID
        Author: JRM <https://metacpan.org/author/JRM>

        This module generates DCE-compatible UUIDs, which according to RFC
        belongs to the legacy variants.

        The benchmark creates 1000+1 random UUIDs.

ACME::CPANMODULES FEATURE COMPARISON MATRIX
     +-------------------------+-----------+-----------+-----------+-----------+-----------+-------+-------+----------------+----------------------+---------------+
     | module                  | create_v1 | create_v2 | create_v3 | create_v4 | create_v5 | is_pp | is_xs | v4_rfc4122 *1) | v4_secure_random *2) | create_legacy |
     +-------------------------+-----------+-----------+-----------+-----------+-----------+-------+-------+----------------+----------------------+---------------+
     | Data::UUID              | yes       | yes       | no        | no        | no        | no    | yes   | N/A            | N/A                  | N/A           |
     | UUID::FFI               | yes       | no        | no        | yes       | no        | no    | yes   | yes            | no                   | N/A           |
     | UUID::Tiny              | yes       | no        | yes       | yes       | yes       | yes   | no    | yes            | no                   | N/A           |
     | UUID::Random            | no        | no        | no        | yes       | no        | yes   | no    | no             | no                   | N/A           |
     | UUID::Random::PERLANCAR | no        | no        | no        | yes       | no        | yes   | no    | yes            | no                   | N/A           |
     | UUID::Random::Secure    | no        | no        | no        | yes       | no        | yes   | no    | yes            | yes                  | N/A           |
     | Crypt::Misc             | no        | no        | no        | yes       | no        | yes   | no    | yes            | yes                  | N/A           |
     | UUID                    | no        | no        | no        | no        | no        | no    | yes   | no             | no                   | yes           |
     +-------------------------+-----------+-----------+-----------+-----------+-----------+-------+-------+----------------+----------------------+---------------+

    Notes:

    1. v4_rfc4122: Whether the generated v4 UUID follows RFC 4122
    specification (i.e. encodes variant and version information in M & N
    positions)
    2. v4_secure_random: Whether the module uses cryptographically secure
    pseudo-random number generator for v4 UUIDs

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

    Data::UUID 1.226

    UUID::FFI 0.11

    UUID::Tiny 1.04

    UUID::Random 0.04

    UUID::Random::PERLANCAR 0.005

    UUID::Random::Secure 0.004

    Crypt::Misc 0.078

    UUID 0.29

BENCHMARK PARTICIPANTS
    *   Data::UUID (perl_code)

        Code template:

         my $u = Data::UUID->new; $u->create for 1..1000; $u->to_string($u->create)

    *   UUID::FFI (perl_code)

        Code template:

         UUID::FFI->new_time for 1..1000; UUID::FFI->new_time->as_hex

    *   UUID::Tiny (perl_code)

        Code template:

         UUID::Tiny::create_uuid() for 1..1000; UUID::Tiny::uuid_to_string(UUID::Tiny::create_uuid())

    *   UUID::Random (perl_code)

        Code template:

         UUID::Random::generate() for 1..1000; ; UUID::Random::generate()

    *   UUID::Random::PERLANCAR::generate (perl_code)

        Code template:

         UUID::Random::PERLANCAR::generate() for 1..1000; UUID::Random::PERLANCAR::generate()

    *   UUID::Random::PERLANCAR::generate_rfc (perl_code)

        Code template:

         UUID::Random::PERLANCAR::generate_rfc() for 1..1000; UUID::Random::PERLANCAR::generate_rfc()

    *   UUID::Random::Secure::generate (perl_code)

        Code template:

         UUID::Random::Secure::generate() for 1..1000; UUID::Random::Secure::generate()

    *   UUID::Random::Secure::generate_rfc (perl_code)

        Code template:

         UUID::Random::Secure::generate_rfc() for 1..1000; UUID::Random::Secure::generate_rfc()

    *   Crypt::Misc (perl_code)

        Code template:

         Crypt::Misc::random_v4uuid() for 1..1000; Crypt::Misc::random_v4uuid()

    *   UUID (perl_code)

        Code template:

         my $uuid; UUID::generate_random($uuid) for 1..1000; UUID::generate_random($uuid); $uuid

BENCHMARK SAMPLE RESULTS
  Sample benchmark #1
    Run on: perl: *v5.38.0*, CPU: *Intel(R) Core(TM) i5-7200U CPU @ 2.50GHz
    (2 cores)*, OS: *GNU/Linux Ubuntu version 20.04*, OS kernel: *Linux
    version 5.4.0-164-generic*.

    Benchmark command (default options):

     % bencher --cpanmodules-module UUID

    Result formatted as table:

     #table1#
     +---------------------------------------+-----------+-----------+-----------------------+-----------------------+-----------+---------+
     | participant                           | rate (/s) | time (ms) | pct_faster_vs_slowest | pct_slower_vs_fastest |  errors   | samples |
     +---------------------------------------+-----------+-----------+-----------------------+-----------------------+-----------+---------+
     | UUID::Random::Secure::generate        |        30 |     30    |                 0.00% |              4218.76% |   0.0013  |      22 |
     | UUID::Random::Secure::generate_rfc    |        40 |     20    |                42.61% |              2928.29% |   0.0003  |      21 |
     | UUID::Random                          |       100 |      9    |               257.90% |              1106.70% |   0.00018 |      20 |
     | UUID::Tiny                            |       100 |      8    |               335.56% |               891.54% |   0.00013 |      20 |
     | UUID                                  |       171 |      5.84 |               481.07% |               643.25% | 1.4e-06   |      21 |
     | Crypt::Misc                           |       296 |      3.37 |               906.43% |               329.12% | 2.6e-06   |      20 |
     | UUID::Random::PERLANCAR::generate_rfc |       520 |      1.9  |              1682.35% |               142.31% | 7.6e-06   |      20 |
     | UUID::Random::PERLANCAR::generate     |       900 |      1    |              2809.14% |                48.45% | 2.5e-05   |      23 |
     | UUID::FFI                             |       870 |      1.2  |              2848.45% |                46.48% | 1.8e-06   |      20 |
     | Data::UUID                            |      1000 |      0.8  |              4218.76% |                 0.00% | 9.3e-06   |      21 |
     +---------------------------------------+-----------+-----------+-----------------------+-----------------------+-----------+---------+

    The above result formatted in Benchmark.pm style:

                 Rate  URS:g  URS:g_r    U:R   U:T     U   C:M  URP:g_r   U:F  URP:g   D:U 
      URS:g      30/s     --     -33%   -70%  -73%  -80%  -88%     -93%  -96%   -96%  -97% 
      URS:g_r    40/s    50%       --   -55%  -60%  -70%  -83%     -90%  -94%   -95%  -96% 
      U:R       100/s   233%     122%     --  -11%  -35%  -62%     -78%  -86%   -88%  -91% 
      U:T       100/s   275%     150%    12%    --  -27%  -57%     -76%  -85%   -87%  -90% 
      U         171/s   413%     242%    54%   36%    --  -42%     -67%  -79%   -82%  -86% 
      C:M       296/s   790%     493%   167%  137%   73%    --     -43%  -64%   -70%  -76% 
      URP:g_r   520/s  1478%     952%   373%  321%  207%   77%       --  -36%   -47%  -57% 
      U:F       870/s  2400%    1566%   650%  566%  386%  180%      58%    --   -16%  -33% 
      URP:g     900/s  2900%    1900%   800%  700%  484%  237%      89%   19%     --  -19% 
      D:U      1000/s  3650%    2400%  1025%  900%  630%  321%     137%   49%    25%    -- 
 
     Legends:
       C:M: participant=Crypt::Misc
       D:U: participant=Data::UUID
       U: participant=UUID
       U:F: participant=UUID::FFI
       U:R: participant=UUID::Random
       U:T: participant=UUID::Tiny
       URP:g: participant=UUID::Random::PERLANCAR::generate
       URP:g_r: participant=UUID::Random::PERLANCAR::generate_rfc
       URS:g: participant=UUID::Random::Secure::generate
       URS:g_r: participant=UUID::Random::Secure::generate_rfc

  Sample benchmark #2
    Benchmark command (benchmarking module startup overhead):

     % bencher --cpanmodules-module UUID --module-startup

    Result formatted as table:

     #table2#
     +-------------------------+-----------+-------------------+-----------------------+-----------------------+-----------+---------+
     | participant             | time (ms) | mod_overhead_time | pct_faster_vs_slowest | pct_slower_vs_fastest |  errors   | samples |
     +-------------------------+-----------+-------------------+-----------------------+-----------------------+-----------+---------+
     | UUID::Random::Secure    |     95    |             88.45 |                 0.00% |              1352.22% |   0.00022 |      20 |
     | UUID::FFI               |     53    |             46.45 |                80.85% |               703.01% |   0.00013 |      20 |
     | UUID::Tiny              |     26.7  |             20.15 |               256.48% |               307.38% | 2.3e-05   |      20 |
     | Crypt::Misc             |     20.9  |             14.35 |               354.68% |               219.40% | 1.9e-05   |      20 |
     | Data::UUID              |     20    |             13.45 |               429.95% |               174.03% |   0.00041 |      20 |
     | UUID                    |     11.4  |              4.85 |               734.65% |                73.99% | 5.5e-06   |      20 |
     | UUID::Random            |      8.9  |              2.35 |               962.94% |                36.62% |   1e-05   |      20 |
     | UUID::Random::PERLANCAR |      8.94 |              2.39 |               964.20% |                36.46% | 7.2e-06   |      20 |
     | perl -e1 (baseline)     |      6.55 |              0    |              1352.22% |                 0.00% | 6.3e-06   |      20 |
     +-------------------------+-----------+-------------------+-----------------------+-----------------------+-----------+---------+

    The above result formatted in Benchmark.pm style:

                              Rate   UR:S   U:F   U:T   C:M   D:U     U  UR:P   U:R  perl -e1 (baseline) 
      UR:S                  10.5/s     --  -44%  -71%  -78%  -78%  -88%  -90%  -90%                 -93% 
      U:F                   18.9/s    79%    --  -49%  -60%  -62%  -78%  -83%  -83%                 -87% 
      U:T                   37.5/s   255%   98%    --  -21%  -25%  -57%  -66%  -66%                 -75% 
      C:M                   47.8/s   354%  153%   27%    --   -4%  -45%  -57%  -57%                 -68% 
      D:U                   50.0/s   375%  165%   33%    4%    --  -42%  -55%  -55%                 -67% 
      U                     87.7/s   733%  364%  134%   83%   75%    --  -21%  -21%                 -42% 
      UR:P                 111.9/s   962%  492%  198%  133%  123%   27%    --    0%                 -26% 
      U:R                  112.4/s   967%  495%  200%  134%  124%   28%    0%    --                 -26% 
      perl -e1 (baseline)  152.7/s  1350%  709%  307%  219%  205%   74%   36%   35%                   -- 
 
     Legends:
       C:M: mod_overhead_time=14.35 participant=Crypt::Misc
       D:U: mod_overhead_time=13.45 participant=Data::UUID
       U: mod_overhead_time=4.85 participant=UUID
       U:F: mod_overhead_time=46.45 participant=UUID::FFI
       U:R: mod_overhead_time=2.35 participant=UUID::Random
       U:T: mod_overhead_time=20.15 participant=UUID::Tiny
       UR:P: mod_overhead_time=2.39 participant=UUID::Random::PERLANCAR
       UR:S: mod_overhead_time=88.45 participant=UUID::Random::Secure
       perl -e1 (baseline): mod_overhead_time=0 participant=perl -e1 (baseline)

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

FAQ
  What is an Acme::CPANModules::* module?
    An Acme::CPANModules::* module, like this module, contains just a list
    of module names that share a common characteristics. It is a way to
    categorize modules and document CPAN. See Acme::CPANModules for more
    details.

  What are ways to use this Acme::CPANModules module?
    Aside from reading this Acme::CPANModules module's POD documentation,
    you can install all the listed modules (entries) using cpanm-cpanmodules
    script (from App::cpanm::cpanmodules distribution):

     % cpanm-cpanmodules -n UUID

    Alternatively you can use the cpanmodules CLI (from App::cpanmodules
    distribution):

        % cpanmodules ls-entries UUID | cpanm -n

    or Acme::CM::Get:

        % perl -MAcme::CM::Get=UUID -E'say $_->{module} for @{ $LIST->{entries} }' | cpanm -n

    or directly:

        % perl -MAcme::CPANModules::UUID -E'say $_->{module} for @{ $Acme::CPANModules::UUID::LIST->{entries} }' | cpanm -n

    This Acme::CPANModules module contains benchmark instructions. You can
    run a benchmark for some/all the modules listed in this
    Acme::CPANModules module using the bencher CLI (from Bencher
    distribution):

        % bencher --cpanmodules-module UUID

    This Acme::CPANModules module also helps lcpan produce a more meaningful
    result for "lcpan related-mods" command when it comes to finding related
    modules for the modules listed in this Acme::CPANModules module. See
    App::lcpan::Cmd::related_mods for more details on how "related modules"
    are found.

HOMEPAGE
    Please visit the project's homepage at
    <https://metacpan.org/release/Acme-CPANModules-UUID>.

SOURCE
    Source repository is at
    <https://github.com/perlancar/perl-Acme-CPANModules-UUID>.

SEE ALSO
    Acme::CPANModules - about the Acme::CPANModules namespace

    cpanmodules - CLI tool to let you browse/view the lists

    RFC 4122, <https://tools.ietf.org/html/rfc4122>

    <https://en.wikipedia.org/wiki/Universally_unique_identifier>

AUTHOR
    perlancar <perlancar@cpan.org>

CONTRIBUTING
    To contribute, you can send patches by email/via RT, or send pull
    requests on GitHub.

    Most of the time, you don't need to build the distribution yourself. You
    can simply modify the code, then test via:

     % prove -l

    If you want to build the distribution (e.g. to try to install it locally
    on your system), you can install Dist::Zilla,
    Dist::Zilla::PluginBundle::Author::PERLANCAR,
    Pod::Weaver::PluginBundle::Author::PERLANCAR, and sometimes one or two
    other Dist::Zilla- and/or Pod::Weaver plugins. Any additional steps
    required beyond that are considered a bug and can be reported to me.

COPYRIGHT AND LICENSE
    This software is copyright (c) 2023, 2021, 2020 by perlancar
    <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.

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

    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.