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Postings from February 2000
In article <200002060004.SAA06395@agogic.cig.mot.com>,
Brad Appleton <bradapp@enteract.com> wrote:
>I also managed to get this working while allowing newlines as
>the separator without too much extra overhead. (At least I think
>so, how bad is it to do: ++$line for (/\n/g); that seems to be
>faster than: $line += split "\n"; anybody have something faster?)
[D:\]perl -w
use Benchmark;
$buf = (join '', map chr, 48..57,65..90,10) x 100;
timethese(20000,
{ for => sub { my $cnt; ++$cnt for $buf =~ m:\n:g; $cnt },
while => sub { my $cnt; ++$cnt while $buf =~ m:\n:g; $cnt },
split1 => sub { my $cnt; $cnt = split /\n/, $buf },
Use of implicit split to @_ is deprecated at - line 7.
split2 => sub { my $cnt; $cnt = (() = split /\n/, $buf, -1)-1 },
tr => sub { my $cnt; $cnt = $buf =~ tr/\n// }
});
__END__
Benchmark: timing 20000 iterations of for, split1, split2, tr, while...
for: 130 wallclock secs (130.45 usr + 0.00 sys = 130.45 CPU) @ 153.32/s (n=20000)
split1: 72 wallclock secs (72.66 usr + 0.00 sys = 72.66 CPU) @ 275.25/s (n=20000)
split2: 77 wallclock secs (77.59 usr + 0.00 sys = 77.59 CPU) @ 257.77/s (n=20000)
tr: 30 wallclock secs (29.60 usr + 0.00 sys = 29.60 CPU) @ 675.68/s (n=20000)
while: 90 wallclock secs (90.83 usr + 0.00 sys = 90.83 CPU) @ 220.19/s (n=20000)
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