Dear monks, I am seeking your wisdom. I have a mod_perl application that searches some databases (custom socket connections, no DBI). The code looks like this: 
sub metasearch {
    my $self = shift;
    my @dbs = @{$self->dbs};

    my @resultset;    
    foreach my $db (@dbs) {
        my $result = $db->do_query;
        push @resultset, $result;
    }
    return \@resultset;
}

[download]

Now I would like the do the "foreach" part in parallel and don't know how.

I had it working fine in a stand alone test script with Parallel::ForkManager but that gave an error when run under mod_perl ("ModPerl::Util::exit: (120000) exit was called at /usr/local/share/perl/5.8.8/Parallel/ForkManager.pm line 306").

Then I read the threading tutorial and was more puzzled than before. Also in Google I couldn't find an example with iteration (I don't know in advance how many and which databases will be needed) and collection of the results. It would also be nice to have a timeout, just in case one of the databases is very slow or even dead.

Any ideas how to (best) do this?

Many thanks
-Michael

In reply to How to do parallel processing within mod_perl by Anonymous Monk

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