HI,
Following is the code for run_on_finish. I am writing data onto disk(/tmp/ directory) retrieved by each child process. and deleting those file after reading them.

$pm->run_on_finish(sub {
        my ($pid, $exit_code, $ident) = @_;
        eval {
        
            my $filename = '/tmp/' . $$ . escape($ident);
            my $result_set;
            
            if (-e $filename) {
                $result_set = $obj->retrieve($filename);
                unlink($filename);
                
            }else {
                # need a new $timeout_result object every loop
                my $timeout_result = new DBWIZ::Search::ResultSet;
                $timeout_result->status('timeout');
                $timeout_result->hits(-5);
                $result_set = $timeout_result;
            }
            $return{$ident} = $result_set;
        
    };
    if ($@) { print STDERR "Problem with search module: $@\n"; }
        
        
        
        # print STDERR "database $ident done = exit $exit_code \n";
    });
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$obj is the Data::Serializer object with following options

my $obj = Data::Serializer->new(
        serializer => 'Storable',
        portable => '1',
        encoding => 'b64',
    );
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