############################################################
#
# ithreads on Centos Linux, 64 bit, 8 CPU's
# Perl v5.10.1 built for x86_64-linux-thread-multi
#    Threads    Clock    CPU    ==>   Speed    Overhead
#    -------    -----    ----         -----    --------
#       1       18.2     18.2   ==>   1.0x         0%
#       2        9.1     18.2   ==>   2.0x         0%
#       3        6.2     18.3   ==>   2.9x         1%
#       5        3.7     18.2   ==>   4.9x         0%
#       8        2.4     18.4   ==>   7.6x         1%
#
# ithreads on my Windows 7, 64 bit, 8 CPU's
# Perl v5.12.3 built for MSWin32-x86-multi-thread
#    Threads    Clock    CPU    ==>   Speed    Overhead
#    -------    -----    ----         -----    --------
#       1       25.0     25.0   ==>   1.0x         0%
#       2       14.6     28.1   ==>   1.7x        12%
#       3       12.9     37.0   ==>   1.9x        48%
#       5        9.9     47.8   ==>   2.5x        91%
#       8        8.2     62.1   ==>   3.0x       148%
#
############################################################

##</code><code>##

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

    my $nr_children = 1;
    my @threads;
    my $start = time;

    foreach my $i (1 .. $nr_children) {
        $threads[$i] = threads->create(\&Work, $i);
    }
    foreach my $i (1 .. $nr_children) {
        $threads[$i]->join();
    }

    my $stop = time - $start;
    printf "\nclock: %.1f sec\n", $stop;
    my @run = times;
    printf "user:  %.1f sec\n", $run[0];

exit;

#####

sub Work {
    my ($i) = @_;

    foreach ( 1 .. (20e5/$nr_children) ) {
        my $acct_nrs = "abc\txyz\tdef\tabc\tghi\tghi";
        my @temp = split(m/\t/, $acct_nrs, -1);
        @temp = ( sort keys %{{ map { $_ => 1 } @temp }} );
        my $ans = join(', ', @temp);
    }
    print " $i";
    return;
}