Hi Monks

I'm playing with MCE::Map to see if it's really faster than native map, but so far, native map seems to be faster...What am I doing wrong? 

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;

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The output is:

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

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When I try the same with the MCE::Map, it takes longer than native map.

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;

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This takes way longer:

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

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When I run this on Perl 5.16.3, both the times are almost double. With 5.32.0 though, I get the outputs given above.

I am trying these on a laptop with Intel(R) Core(TM) i5-3210M CPU @ 2.50GHz Processor and 16 GB RAM running Debian Buster with backported kernel as shown below:

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

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In reply to Native Map faster than MCE::Map. by Anonymous Monk

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