And if every worker fork needs to modify 1 bit on every 4x page of 1 GB of shared data, it's gonna take forever.

Rubbish

use strict;
use warnings;
use 5.010;
use Time::HiRes qw(time);

my $data = 'x' x 500_000_000;
my $t = time;
$data =~ tr/x/y/;
say time - $t;
__END__
0.469923973083496

[download]
use strict;
use warnings;
use 5.010;
use Time::HiRes qw(time);

my $data = 'x' x 500_000_000;
my $t    = time;
unless (fork) {
    $data =~ tr/x/y/;
    exit;
}
wait;
say time - $t;
__END__
0.765344142913818

[download]
use strict;
use warnings;
use 5.010;
use threads;
use Time::HiRes qw(time);

my $data = 'x' x 500_000_000;
my $t    = time;
threads->create(
    sub {
        $data =~ tr/x/y/;
    }
)->join;
say time - $t;
__END__
1.29563307762146

[download]

In reply to Re^21: Strange memory leak using just threads (forks.pm) by zwon
in thread Strange memory leak using just threads by MnkyBrain

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