in reply to Re: Multithreaded memory usage
in thread Multithreaded memory usage

Okay,

I have tried the for method and after about 60 forks (over 5 mins) the parent process can't fork any more processes. I have tried setting $SIG{CHLD} = 'IGNORE' to ignore the zombified children, but to no avail.

Any ideas where to go to next?

Cheers!

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Re^3: Multithreaded memory usage
by Corion (Patriarch) on Apr 21, 2009 at 14:06 UTC

    On Windows, start the subprocess not via fork() but better via system(1, @args) or via system("start @args");. That way, it is dissociated from the main Perl program.

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Re^3: Multithreaded memory usage
by moritz (Cardinal) on Apr 21, 2009 at 13:51 UTC
    wait (or waitpid) for them (perhaps in $SIG{CHLD} to be nearly non-blocking) so that they don't become zombies? And what's the error message?
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      This is a simplified code version, it can't fork any more processes after 64 loops ($pid is undefined): 
      use LWP::Simple;

my @pid;
for(my $i = 0; $i < 720; $i++){
  print "$i\n";
  $pid[$i] = fork();
  if (not defined $pid[$i]) {
    print "resources not avilable.\n";
  } 
  elsif($pid[$i] == 0) {
    get_data_and_go();
    exit(0);
  }
  else{
    sleep 2;
  };
};
sub get_data_and_go {
  does some webpage stuff and exits
  exit(0);
};

      [download]
      Question is will the wait function actually pause the program? (which is what I don't want).

      Cheers!

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