AriSoft has asked for the wisdom of the Perl Monks concerning the following question:

Hello Monks,

Is there any new wisdom available about this old problem? 

use threads;
threads->create(sub {})->join while 1;

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This simple code leaks memory when tested on Debian Lenny v5.10.0 and also with v5.10.1. It has also been discussed here some years ago.

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Re: Status of memory leak problem?
by BrowserUk (Patriarch) on Apr 03, 2010 at 19:21 UTC

    What do you see if you run this? 

    #! perl -slw
use strict;
use threads;
use threads::shared;
use Time::HiRes qw[ time ];

my $count :shared = 0;

async{
    my $last = $count;
    while( sleep 1 ) {
        my $now = $count;
        printf "%d threads/second\n", $now - $last;
        $last = $now;
    }
}->detach;

threads->create(
    sub { lock $count; ++$count; }
)->join while 1;

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    Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
    "Science is about questioning the status quo. Questioning authority".
    In the absence of evidence, opinion is indistinguishable from prejudice.
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[d/l]

      I see RSS growing about 1M per second with 5.10.1 and 5.12.0-RC1, and about 1M per 3 seconds with 5.8.9

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        Which platform, and what output from the program?

        Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
        "Science is about questioning the status quo. Questioning authority".
        In the absence of evidence, opinion is indistinguishable from prejudice.
[reply]
Re: Status of memory leak problem?
by Anonymous Monk on Apr 03, 2010 at 18:16 UTC
    Maybe you can link previous discussion /bug report? It doesn't leak on win32 5.10.1.
[reply]
      Yes, You are right - it does not leak in Windows. Unfortinately sockets does not work properly threaded in windows and threads leaks memory in Linux. No system is perfect for threaded socket programming :-) One old discussion is Perl Threads and Memory Leaking and there are others too.
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