The following are parallel demonstrations using MCE::Hobo and threads.

MCE::Hobo and MCE::Shared

A Hobo is a migratory worker inside the machine that carries the asynchronous gene. Hobos are equipped with threads-like capability for running code asynchronously. Unlike threads, each hobo is a unique process to the underlying OS. The IPC is managed by MCE::Shared, which runs on all the major platforms including Cygwin.

use strict;
use warnings;

use MCE::Hobo;
use MCE::Shared;
use Time::HiRes qw[ time ];

my $start = time;
my $fh    = MCE::Shared->handle( "<:raw", $ARGV[ 0 ] );
my $seen  = MCE::Shared->array;

sub task {
   my @_seen;
   while( read( $fh, my $buf, 16384 * 4 ) ) {
      # the length check may be omitted with MCE::Shared 1.002+
      last unless length($buf);
      ++$_seen[$_] for unpack 'C*', $buf;
   }
   for ( 0 .. 255 ) {
      $seen->incrby($_, $_seen[$_]) if $_seen[$_];
   }
}

MCE::Hobo->create('task') for 1 .. 8;

# do other stuff if desired

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

close $fh;

printf "Took %f secs\n", time() - $start;

# export and destroy the shared array into a local non-shared array

$seen = $seen->destroy;

# for ( 0 .. 255 ) {
#    printf "%c : %u\n", $_, $seen->[$_] if $seen->[$_];
# }
[download]

threads and MCE::Shared

The code for MCE::Hobo and threads are very similar.

use strict;
use warnings;

use threads;
use MCE::Shared;
use Time::HiRes qw[ time ];

my $start = time;
my $fh    = MCE::Shared->handle( "<:raw", $ARGV[ 0 ] );
my $seen  = MCE::Shared->array;

sub task {
   my @_seen;
   while( read( $fh, my $buf, 16384 * 4 ) ) {
      # the length check may be omitted with MCE::Shared 1.002+
      last unless length($buf);
      ++$_seen[$_] for unpack 'C*', $buf;
   }
   for ( 0 .. 255 ) {
      $seen->incrby($_, $_seen[$_]) if $_seen[$_];
   }
}

threads->create('task') for 1 .. 8;

# do other stuff if desired

$_->join for threads->list;

close $fh;

printf "Took %f secs\n", time() - $start;

# export and destroy the shared array into a local non-shared array

$seen = $seen->destroy;

# for ( 0 .. 255 ) {
#    printf "%c : %u\n", $_, $seen->[$_] if $seen->[$_];
# }
[download]

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