Enlightened Monks,

I am writing a Bioinformatics grid service in perl where I use various computers to process parts of a BLAST (bioinformatics algorithm file). My program creates a thread to send work to a node and as the node ends his work, so should the thread. Since the program will be dealing with many nodes, thus creating and destroying many threads, memory is a big deal. I have noticed that each time a create and destroy a thread, my precious megabytes seem to leak! Below may be found a simpler version where the leak occurs. Please help me find the light.

Thanks,
Paulo Carvalho

#!/usr/bin/perl-w

#Libs
use strict; use threads; use threads::shared;
my %thr; #Threads controling each node
my %thr_up;  share (%thr_up); #if thread finished job $thr_up shuould 
+be = 0


SMALL:for (1 .. 1000) {
    
    #Find a waiting thread
    unless ($thr_up{"FREE_HOST"}) {
        $thr_up{"FREE_HOST"} = 1; #thread working flag
        $thr{"FREE_HOST"} = threads->create("blast_thread");
        sleep(1);
        
        my @list = threads->list();
        $list[scalar(@list-1)]->join () if (scalar(@list) > 2);
        foreach my $l (@list) {print "$l\n";}
        
    }
    #Just for my surprise:
    print $thr{FREE_HOST}->tid, ",$thr{FREE_HOST} \n" if ($thr{FREE_HO
+ST}->tid);
}

sub blast_thread {

    $thr_up{FREE_HOST} = 0;
    print "Server UP\n";
    return;
}

############################

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In reply to A Memory Leak in Perl iThreads? by Anonymous Monk

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