linux memory leak monitor

After starting to do Tk programming, I realized how easy it is to make a lousy design which leaks memory, especially with photo objects. So I got tired of running top and peeking back and forth, or repeatedly running ps.

After looking at all the alternatives, I settled on directly reading from /proc. It seemed to run the best out of all tried methods, which I monitored with strace. Look in the upper left corner.

UPDATE May-7-2005 added a MeM.pm version

UPDATE July 12 2011 fixed the way pid is obtained for Perl 5.14.1. $$ is gone, replaced with POSIX::getpid()

#!/usr/bin/perl use warnings; use strict; use Tk; use POSIX qw(getpid); #update for Perl 5.14.1 ########################################################## # you can put it in your development programs like this: # my $memmonitor = 1; # if($memmonitor){ # my $pid = $$; # if(fork() == 0){exec("./memmonitor $pid")} # } ###################################################### #my $pid = shift || $$; my $pid = getpid(); my $mw = new MainWindow; $mw->overrideredirect(1); my $t = $mw->Label(-text=>'', -bg=>'black', -fg=>'yellow')->pack; my $id = Tk::After->new($mw,1000,'repeat',\&refresh); MainLoop; sub refresh{ my @size = split "\n", `cat /proc/$pid/status`; (my $vmsize) = grep {/VmSize/} @size; my (undef,$size) = split "\t",$vmsize; $t->configure(-text=>"PID: $pid -> $size"); if($size eq ''){Tk::exit} } __END__ ################################################# Here is a modular version, save the file below as MeM.pm package MeM; use warnings; use strict; use POSIX qw(getpid); #my $pid =$$; my $pid = getpid(); if (fork() == 0) { require Tk; my $mw = new MainWindow; $mw->overrideredirect(1); $mw->geometry('-0-0'); my $t = $mw->Label(-text => '', -bg => 'black', -fg => 'yellow')-> +pack; $0 = 'MeM'; my $id = Tk::After->new($mw, 1000, 'repeat', [ \&refresh, $pid ]); Tk::MainLoop(); sub refresh { my $pid = shift; #asmutils version of cat # my @size = split "\n", `/home/zentara/perl5lib/cat /proc/$pid +/status`; my @size = split "\n", `cat /proc/$pid/status`; (my $vmsize) = grep { /VmSize/ } @size; my (undef, $size) = split ' ', $vmsize; $t->configure(-text => "PID: $pid -> $size"); if ($size eq '') { exit } } } 1;
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Re: linux memory leak monitor by onkhector (Novice) on Mar 17, 2004 at 03:15 UTC
You can also monitor programs in (horror!) other languages by doing smething like this: `my $command = shift; my $pid = fork(); unless (0 == $pid){ ...Tk code... }else{ exec($command); }` [download] You now pass the program name instead of the PID to the script.	[reply] [d/l]
Re: linux memory leak monitor by duelafn (Parson) on Mar 17, 2004 at 02:08 UTC
You might want to change the extraction line so that your code still works for programs over 100MB. sub refresh{ my @size = split "\n", `cat /proc/$pid/status`; (my $vmsize) = grep {/VmSize/} @size; my ($size) = $vmsize =~ /VmSize:\s+(.*)$/; # Changed this $t->configure(-text=>"PID: $pid -> $size"); if($size eq ''){Tk::exit} } [download]	[reply] [d/l]
Re: linux memory leak monitor by zentara (Archbishop) on Mar 17, 2004 at 19:28 UTC
duelafn said: You might want to change the extraction line so that your code still works for programs over 100MB. `my ($size) = $vmsize =~ /VmSize:\s+(.*)$/;` [download] Good point, I looked at it with a hex editor, and it seems that it should be a tab `(my $vmsize) = grep {/VmSize/} @size; my (undef,$size) = split "\t",$vmsize;` [download] I'm not really a human, but I play one on earth. flash japh	[reply] [d/l] [select]


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