#!/usr/bin/env perl

use 5.016;
use warnings;

use MCE;

my $total_logical_cores = MCE::Util::get_ncpu();
my $auto_max_workers;

{
    my $mce_temp = MCE::->new(max_workers => 'auto');
    $auto_max_workers = $mce_temp->max_workers();
    $mce_temp->shutdown;
}

my $auto_to_ncpu_mult = $total_logical_cores / $auto_max_workers;
my @percentages = qw{0 20 25 33.333 40 50 60 66.667 75 80 100 200};

for my $percentage (@percentages) {
    say "Specified percentage of logical cores to use: $percentage%";
    $percentage = 1 if $percentage <= 0;
    say "Modified percentage of logical cores to use: $percentage%";
    say 'Total number of logical cores ', MCE::Util::get_ncpu();
    my $auto_max_workers = 'auto*' . $auto_to_ncpu_mult * $percentage / 100;
    say "Auto max_workers: $auto_max_workers";

    my @wids;

    my $mce = MCE::->new(
        max_workers => $auto_max_workers,
        gather => \@wids,
        user_func => sub {
            my ($mce) = @_;
            MCE->gather($mce->wid);
        },
    );

    $mce->run();

    say "Worker ID(s): @{[sort { $a <=> $b } @wids]}";
}