Indeed I tried that one, and you're right I should have been a
bit more specific.
It does exactly what I want it to do, at least the example
code.
The moment I start messing around by, say, adding a home-brew
module (which contains really nothing special but some
common stuff to be re-used by other scrips), it 'misbehaves'.
This misbehaviour means that when I specify a processqueue
of 10, it runs 10 processes, but does not respawn new ones.
At the end just 10 processes have run and
finished.
The examplecode I use is mostly from the book, slightly customized: 
#perl.exe -w

# INIT ----
use strict;
use Parallel::ForkManager;
use MyTest; # Mind this one, it's the one that messes things up

# VARS ----
my $max_procs = 10;
my $wait = 5;
my @collections = qw( adw adw_wet_compleet ag-dou ag-gi ag-hc ag-hlo a
+g-its-sol ag-its-sol-hot agents alg_diversen alg_dossier_juris_en_res
+o alg_ellis alg_ellis_en alg_kb alg_kfb alg_kluwer_rest alg_pdf alg_r
+est alg_sdu am b_adw b_adw_wet_compleet b_ag-dou b_ag-gi b_ag-hc b_ag
+-hlo b_ag-its-sol b_ag-its-sol-hot b_agents b_alg_diversen b_alg_doss
+ier_juris_en_reso b_alg_ellis b_alg_ellis_en b_alg_kb b_alg_kfb b_alg
+_kluwer_rest b_alg_pdf b_alg_rest b_alg_sdu b_am b_bibliotheek b_bm b
+_bna-mix b_browsedocs b_curbel b_fmod b_help b_hvg b_hvg-kluwer b_mrp
+ b_pz b_refdocs b_tss b_tss-pdf bibliotheek bm bna-mix  browsedocs cu
+rbel fmod help hvg hvg-kluwer images mrp pz refdocs tss tss-pdf );



# MAIN ----
my $pm =  new Parallel::ForkManager($max_procs);

# Setup a callback for when a child finishes up so we can
# get it's exit code
$pm->run_on_finish(
    sub { my ($pid, $exit_code, $ident) = @_;
        print "** $ident finished (PID: $pid) and exit code: $exit_cod
+e\n";
    }
);

$pm->run_on_start(
    sub { my ($pid,$ident)=@_;
        print "** $ident started, pid: $pid\n";
    }
);

$pm->run_on_wait(
    sub {
        print "** waiting\n";
    }, 0.5
);

foreach my $child ( 0 .. $#collections ) {
    my $pid = $pm->start($collections[$child]) and next;
    
    # This code is the child process
    print "Child: $collections[$child]\n";
    sleep $wait;
    # End of child process
    
    $pm->finish($child); # pass an exit code to finish
}

print "Waiting for Children...\n";
$pm->wait_all_children;
print "Everybody is out of the pool!\n";

[download]
I pin-pointed the problem, try this for the 'MyTest' module... 
package MyTest;

#---------------------------------------------------------------------
+---
#                                  INIT
#---------------------------------------------------------------------
+---
use strict;
use Win32::OLE;
use Win32::OLE::Variant;

1;

[download]

This will show the problem as mentioned above.
Needs some meditation, does it? :-)

In reply to Re^2: Parallel tasks by john.goor
in thread Parallel tasks by john.goor

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