Hi brothers,

I tried to understand fork. I think that I basically got the
theory behind it, but am far away from practical usage of this
nifty feature. What do I want to achieve? I want to simply harness
the power of SMP machines - just use all the nice BogoMIPS for
computational intensive tasks.

My first shot at it was Parallel::ForkManager:

use Parallel::ForkManager; # Yadda yadda
local %hash;
$pm = new Parallel::ForkManager(2); # Want use 2 CPUs now (###)

foreach $thingy (@so_30_member_list) {
  my $pid = $pm->start and next;  # (###)
  $hash{$thingy} = &big_heavy_computation_of($thingy);
  $pm->finish; # Terminates the child process (###)
}

&look_at_hash;

[download]
While this is really great because the loop just takes half
of the time to compute, it is not so great, because the hash
is very empty then. If I remove the (###) lines, the program
takes twice as long, but the hash is ok.

So now for me to better understand this. I assume, that with
the $pm->start and next a new child is forked with
completedly his own data, thus filling his own instance
of %hash, and then ... well ... just discarding it.

This isnīt actually what I want. How can I get the computer doing
what I want and not what Iīm telling him? :-)

Any help apreciated

Ciao

In reply to FORRRRRK again... by PetaMem

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