This should work anywhere including cygwin:

use threads;
use Threads::Queue;

my $Q = new Thread::Queue;
my $thread = async {

    ## create/open DB here

    my $dbs = ...;
    while( my $query = $Q->dequeue ) {
        $dbs->query( $query );
    }

    ## finish with DB here

};

while (<I>) {
    
    my $line = $_;
    my @bucket = $bucket->based_on($line); # Data::Bucket
    my @acct_vals;
 
    for (@bucket) {
        # %hash = calculate based on input and bucket value
        push @acct_vals, \%hash;
    }

    next unless @acct_vals;

    @acct_vals = 
      map { $_->[0] }
    sort { $a->[1] <=> $b->[1] } 
      map { [ $_, $_->{dist} ] } @acct_vals;

    my @dump ;
    for my $acct_val (@acct_vals) {
      last if $acct_val->{dist} > $match_threshold * 1.5 ;
      push @dump, $acct_val;
    }

    my $d = Data::Dumper->new([\@dump], ['dump']) ;
    $d->Purity(1)->Terse(1)->Deepcopy(1);

    ## Build sql and post to db thread (Could be done better)
    my $args = "'" . join( "','", $acct_name, $clean_acct_name, $d->Du
+mp) . "'";

    sleep 1 while $Q->pending > 10; ## Adjust threshhold to suit.
    $Q-enqueue( sprintf 'INSERT INTO addresses VALUES (%s)', $args );

    unless (++$counter % $report_very) {
      warn "$counter in $now"; # Time::Lapse by Scott Godin
    }

}
$Q->enqueue( undef ); ## Terminate db thread
$thread->join;        ## And wait for it to finish.
[download]