use strict;
use warnings;
use Time::HiRes qw (gettimeofday tv_interval);

my @bignum = (1..100000000);

my $native_map_start_time = [gettimeofday];
my @native_map = map { $_ * $_ } @bignum;
my $native_elapsed_time = tv_interval($native_map_start_time);

printf "The elapsed time with native map is %2.2f seconds\n", $native_elapsed_time;

##</code><code>##

$ perl native_map.pl 
The elapsed time with native map is 8.57 seconds

##</code><code>##

use strict;
use warnings;
use MCE::Map;
use Time::HiRes qw (gettimeofday tv_interval);

my $mce_start_time = [gettimeofday];
my @mce_map = mce_map_s { $_ * $_ }1, 100000000;
my $mce_elapsed = tv_interval($mce_start_time);

printf "The elapsed time with MCE::map (mce_map_s) is %2.2f seconds\n", $mce_elapsed;

##</code><code>##

perl mce_map.pl 
The elapsed time with MCE::map (mce_map_s) is 25.34 seconds

##</code><code>##

uname -rv
5.10.0-0.bpo.7-amd64 #1 SMP Debian 5.10.40-1~bpo10+1 (2021-06-04)