in reply to Cleaning up threads so they do not leak memory. (Win32)

I played a bit with your code, and I just want to register my confusion on a couple of matters. First, on this:
foreach my $thr (threads->list) {
    # Don't join the main thread or ourselves
     if ($thr->tid && !threads::equal($thr, threads->self)) {
         $thr->join;
            }
        }

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The main thread has an id of "0", and threads->list doesn't seem to return thread 0, so I wonder if that's a bug in the list() method, or if the conditional before the join is unnecessary.

Second, on this:

    my $GetProcessMemoryInfo = Win32::API->new('psapi','GetProcessMemo
+ryInfo', ['I', 'P', 'I'], 'I') or return $^E;

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I thought it was a waste linking to that function on every call to it, so I tried to move it (and the other Win32::API function definition), to near the top of the program, but it ended up crashing perl. If I defined it near the top, and still defined it again on every call, it worked a couple of times, but then returned "The specified module could not be found" trying to link to it again after joining the threads.

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Re^2: Cleaning up threads so they do not leak memory. (Win32)
by BrowserUk (Patriarch) on Feb 24, 2006 at 10:10 UTC

    You might find this version of the OP code useful--or not:)

    It uses tasklist.exe to get the memory stat rather than Win32::API as I have had great problems with using that module with threads in the past and despite several attempts to work out why, my XS foo isn't strong enough. 

    #! perl -slw
use strict;
use threads;

sub mem {
    my( $usage ) =  `tasklist /NH /FI \"pid eq $$\" ` =~ m[ (\S+) \s+ 
+K \s* $ ]x;
    return $usage;
}

sub threadTest{ sleep 1 }

my $startmem = mem;
print "StartMem: $startmem KB";

for my $pass ( 1 .. 50 ) {
    my @threads = map{
        Win32::Sleep 100;
        threads->new(\&threadTest);
    } 1 .. 25;

    my $midmem = mem;

    $_->join for @threads;
    undef @threads;

    my $endmem = mem;
    print "Pass $pass\tMidMem: $midmem KB\tEndMem: $endmem KB";
}

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