I find Parallel::ForkManager good for this kind of thing as it lets you write: 
use Parallel::ForkManager;
$pm = new Parallel::ForkManager($MAX_PROCESSES);
foreach $data (@all_data) {
    # Forks and returns the pid for the child:
    my $pid = $pm->start and next; 

    ... do some work with $data in the child process ...

    $pm->finish; # Terminates the child process
}

[download]
Code stolen from docs :)

gav^

In reply to Re: Many children, but never more than a fixed number at once. by gav^
in thread Many children, but never more than a fixed number at once. by Abigail-II

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