Serial    threads  MCE::Hobo  MCE::Loop  MCE::Child

Linux      74.488s    25.345s    20.217s    17.932s     17.291s
macOS      84.010s    24.844s    24.505s    23.786s     23.069s
Windows   102.055s    29.702s    37.913s    28.376s     27.839s
Cygwin    162.474s    -------    50.092s    45.318s     43.949s
FreeBSD   107.569s    -------    31.138s    30.530s     30.050s

   threads is slow on Cygwin, so stopped due to taking too long.
   My FreeBSD has an older Thread::Queue missing the ->end method.


##</code><code>##

use strict;
use warnings;
use Time::HiRes 'time';

my @tokens = ('aaa'...'zzz');
my $start  = time;

sub build_regex {
    my ($token) = @_;
    chop $token;
    $token .= 'a';
}

my %result;

foreach my $token ( @tokens ) {
    my $regex = build_regex($token);
    my @line_results = grep { $_ ne $token and /$regex/ } @tokens;
    $result{$token} = \@line_results if @line_results;
};

printf "duration: %0.03f seconds\n", time - $start;
print scalar(keys %result), "\n"; # 16900


##</code><code>##

use strict;
use warnings;
use threads;
use Thread::Queue;
use Time::HiRes 'time';

my $workQueue  = Thread::Queue->new();
my $doneQueue  = Thread::Queue->new();
my $numWorkers = 4;

my @tokens = ('aaa'...'zzz');
my $start  = time;

sub build_regex {
    my ($token) = @_;
    chop $token;
    $token .= 'a';
}

threads->create(sub{DoWork($workQueue, $doneQueue)}) for 1..$numWorkers;

$workQueue->enqueue($_) for @tokens;
$workQueue->end();

my $count_finished = 0;
my %result;

while () {
    my ($key, $val) = $doneQueue->dequeue(2);
    last if (!$key && ++$count_finished == $numWorkers);
    $result{$key} = $val if $key;
}

$_->join() for threads->list;

printf "duration: %0.03f seconds\n", time - $start;
print scalar(keys %result), "\n"; # 16900

exit;

sub DoWork {
    my ($work, $done) = @_;
    while (my $token = $work->dequeue()) {
        my $regex = build_regex($token);
        my @line_results = grep { $_ ne $token and /$regex/ } @tokens;
        $done->enqueue($token => \@line_results) if @line_results;
    }
    $done->enqueue(0,0);
}


##</code><code>##

use strict;
use warnings;
use MCE::Hobo;
use MCE::Shared;
use Time::HiRes 'time';

my $workQueue  = MCE::Shared->queue();
my $doneQueue  = MCE::Shared->queue();
my $numWorkers = 4;

my @tokens = ('aaa'...'zzz');
my $start  = time;

sub build_regex {
    my ($token) = @_;
    chop $token;
    $token .= 'a';
}

MCE::Hobo->create(sub{DoWork($workQueue, $doneQueue)}) for 1..$numWorkers;

$workQueue->enqueue($_) for @tokens;
$workQueue->end();

my $count_finished = 0;
my %result;

while () {
    my ($key, $val) = $doneQueue->dequeue(2);
    last if (!$key && ++$count_finished == $numWorkers);
    $result{$key} = $val if $key;
}

$_->join() for MCE::Hobo->list;

printf "duration: %0.03f seconds\n", time - $start;
print scalar(keys %result), "\n"; # 16900

exit;

sub DoWork {
    my ($work, $done) = @_;
    while (my $token = $work->dequeue()) {
        my $regex = build_regex($token);
        my @line_results = grep { $_ ne $token and /$regex/ } @tokens;
        $done->enqueue($token => \@line_results) if @line_results;
    }
    $done->enqueue(0,0);
}


##</code><code>##

use strict;
use warnings;
use MCE::Loop;
use Time::HiRes 'time';

my @tokens = ('aaa'...'zzz');
my $start  = time;

sub build_regex {
    my ($token) = @_;
    chop $token;
    $token .= 'a';
}

MCE::Loop->init(
    chunk_size  => 1,
    max_workers => 4,
);

my %result = mce_loop {
    my $token = $_;
    my $regex = build_regex($token);
    my @line_results = grep { $_ ne $token and /$regex/ } @tokens;
    MCE->gather( $token => \@line_results ) if @line_results;
} @tokens;

MCE::Loop->finish;

printf "duration: %0.03f seconds\n", time - $start;
print scalar(keys %result), "\n"; # 16900


##</code><code>##

use strict;
use warnings;
use MCE::Child;
use MCE::Channel;
use Time::HiRes 'time';

my $workQueue = MCE::Channel->new(impl => 'Mutex');
my $numWorkers = 4;

my @tokens = ('aaa'...'zzz');
my $start  = time;

sub build_regex {
    my ($token) = @_;
    chop $token;
    $token .= 'a';
}

MCE::Child->create(sub{DoWork($workQueue)}) for 1..$numWorkers;

$workQueue->enqueue($_) for @tokens;
$workQueue->end();

my %result = map { %{ $_->join() } } MCE::Child->list;

printf "duration: %0.03f seconds\n", time - $start;
print scalar(keys %result), "\n"; # 16900

exit;

sub DoWork {
    my ($workQueue) = @_;
    my %result; # store locally
    while (my $token = $workQueue->dequeue()) {
        my $regex = build_regex($token);
        my @line_results = grep { $_ ne $token and /$regex/ } @tokens;
        $result{$token} = \@line_results if @line_results;
    }
    return \%result;
}