Inside of Time::Strptime

Shibuya.pm #18 LT

Transcript

1. Inside of
   Time::Strptime
   id:karupanerura
   Shibuya.pm #18 LT
   

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2. Time::Strptime
   

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3. use Time::Strptime qw/strptime/;
   # function
   my ($epoch_f, $offset_f)
   = strptime('%Y-%m-%d %H:%M:%S', '2014-01-01 00:00:00');
   # OO style
   my $fmt = Time::Strptime::Format->new('%Y-%m-%d %H:%M:%S');
   my ($epoch_o, $offset_o)
   = $fmt->parse('2014-01-01 00:00:00');
   Time::Strptime
   

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4. Time::Strptime
   • strptime(3) ͷ Pure Perl ࣮૷
   • Time::MomentͰ೚ҙϑΥʔϚοτͷύʔε͕
   Ͱ͖ͳ͔ͬͨͷͰ࡞ͬͨ
   • ߴ଎
   

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5. Pure Perlͳͷʹߴ଎ʁʁʁ
   

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6. ϕϯνϚʔΫ
   

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7. ৚݅
   • OS X High Sierra
   • Perl 5.28.0
   • Time::Local: 1.28
   • Time::Moment: 0.44
   • Time::Piece: 1.3204
   • Time::Strptime: 1.03
   

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8. ৚݅
   • %Y-%m-%d %H:%M:%S Ͱparse͢Δ
   • epochͱoffsetΛऔಘ
   • Parser͸Ωϟογϡͯ͠ྑ͍(cachedͱ໌ه)
   • GMTͰ࣮ߦ(offsetܭࢉͷ࠷దԽ͸Մೳ)
   

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9. Benchmark: running pt, tm, tp, tp(cached), ts(cached) for at least 10 CPU seconds...
   pt: 11 wallclock secs (10.41 usr + 0.01 sys = 10.42 CPU) @ 297345.59/s (n=3098341)
   tm: 10 wallclock secs (10.17 usr + 0.01 sys = 10.18 CPU) @ 2481673.28/s (n=25263434)
   tp: 10 wallclock secs (10.52 usr + 0.01 sys = 10.53 CPU) @ 56390.98/s (n=593797)
   tp(cached): 11 wallclock secs (10.53 usr + 0.01 sys = 10.54 CPU) @ 80838.24/s (n=852035)
   ts(cached): 11 wallclock secs (10.60 usr + 0.01 sys = 10.61 CPU) @ 267686.15/s (n=2840150)
   Rate tp tp(cached) ts(cached) pt ™
   tp 56391/s -- -30% -79% -81% -98%
   tp(cached) 80838/s 43% -- -70% -73% -97%
   ts(cached) 267686/s 375% 231% -- -10% -89%
   pt 297346/s 427% 268% 11% -- -88%
   tm 2481673/s 4301% 2970% 827% 735% --
   tp=Time::Piece(XS)
   ts=Time::Strptime(PP)
   pt=POSIX::strptime
   tm=Time::Moment(XS)
   

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10. ݁Ռ
    • Time::Piece(cached)ʹରͯ͠231%ߴ଎
    • POSIX::strptimeʹରͯ͠10%௿଎
    • ※DateTime͸ൺֱͷܻ͕ҧ͏ͷͰআ֎ͯ͠Δ
    • ͓ͦ͗͢Δ
    

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11. ͳͥ଎͍ʁ
    

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12. Ξϓϩʔν
    • ࠷దԽͨ͠ίʔυΛੜ੒ͯ͠Ωϟογϡ
    • ෼ذͱϝϞϦΞϩέʔγϣϯΛ࠷খԽ
    • ಉ͡Ξϓϩʔνͷ࣮૷
    • Text::MicroTemplate
    • Apache::LogFormat::Compiler
    

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13. ੜ੒ίʔυྫ
    my ($year, $month, $day, $hour24, $minute, $second,
    $offset, $epoch);
    $offset = 0;
    sub {
    ($year, $month, $day, $hour24, $minute, $second) =
    $_[0] =~ m{\A([0-9]{4})\-(0[1-9]|1[0-2])\-(0[1-9]|[12]
    [0-9]|3[01])T([01][0-9]|2[0-3])\:([0-5][0-9])\:([0-5][0-9]|
    60)\z}mo
    or Carp::croak 'cannot parse datetime. text: "'.
    $_[0].'", format: '."\"%FT%T\"";
    $epoch = timegm_nocheck($second, $minute, $hour24,
    $day, $month - 1, $year);
    $offset = $time_zone->offset($epoch);
    $epoch -= $offset;
    ($epoch, $offset);
    };
    

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14. ͜ΕΛText Evalͯ݁͠Ռͷ
    CodeRefΛΩϟογϡ
    

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15. ଎͍ʂʂʂʂʂʂ
    

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16. ·ͱΊ
    eval͸ศར
    

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17. ͋Γ͕ͱ͏͍͟͝·ͨ͠
    

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