my %pool; my %dbhs; $MAX = 5; $pm->run_on_start(\&_child_start); $pm->run_on_finish(\&_child_finish); my @dbhs = start_dbh(); %pool = map { $_ => 1 } @dbhs; foreach $i ( @is ) { ($next) = grep ( defined($pool{$_}), @dbhs ); $pid = $pm->start($next) and next; $sys->set_dbh($dbhs{$next}); sleep(rand(10)); $pm->finish; } sub start_dbh() { %dbhs = map { $_ => DBI::Connect(); } 0 .. $MAX; return keys %dbhs; } Sys::set_dbh() { my $this = shift; $this->{'_dbh-child'} = shift; } sub _child_start() { my ($pid, $ident) = @_; delete($pool{$ident}); print "**** STARTED: child with PID $pid"; } sub _child_finish(){ my ($pid, $exit, $ident) = @_; print "**** FINISHED: child with PID $pid exit cide $exit"; $pool{$ident} = 1; }