Re: [Caml-list] Tracking memory usage: GC output not same order as unix top command

[Richard Jones <rich@annexia.org>]

On Mon, Aug 30, 2010 at 11:33:48AM +0100, Hugo Ferreira wrote:
> I looked at this tool. Going to ask the admin if he can install
> this because I cannot interpret the output from the "/proc/<pid>/maps".

Here's a Perl script that I wrote quite a long time ago.  I don't know
if it still works, but worth looking at.

Rich.

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#!/usr/bin/perl -wT
# Parse /proc/*/maps file into a readable summary.
# $Id: maps.pl,v 1.1 2006/11/01 10:35:56 rich Exp $

no warnings qw(portable);

foreach my $filename (@ARGV) {
  my %devices;

  open MAPS, "<$filename" or die "$filename: $!";

  while (<MAPS>) {
    if (m/^([[:xdigit:]]+)-([[:xdigit:]]+) ([-rwxps]+) ([[:xdigit:]]+) ([[:xdigit:]]{2}:[[:xdigit:]]{2}) (\d+)\s*(.*)?/) {
      my $start = hex $1;
      my $end = hex $2;
      my $perms = $3;
      my $offset = hex $4;
      my $device = $5;
      my $inode = $6;
      my $filename = $7;

      my $size = $end - $start;

      # Create a record.
      my %rec =
	(
	 start => $start,
	 end => $end,
	 perms => $perms,
	 offset => $offset,
	 device => $device,
	 inode => $inode,
	 filename => $filename,
	 size => $size
	);

      # Key for storing this.
      my $key;
      if ($device ne "00:00" && $inode != 0) {
	$key = "$filename ($device $inode)"
      } elsif ($filename ne "") {
	$key = $filename
      } else {
	$key = "anonymous mapping"
      }

      # Store it.
      $devices{$key} = [] if !exists $devices{$key};
      push @{$devices{$key}}, \%rec
    } else {
      warn "ignored: $_\n"
    }
  }

  close MAPS;

  # Get the list of devices.
  my @devices = keys %devices;

  # For each device, print a summary.
  foreach (@devices) {
    print "$_:\n";
    my @recs = @{$devices{$_}};
    my $sum = 0;
    $sum += $_->{size} foreach @recs;
    printf ("  %d bytes %.1f MB\n", $sum, $sum/1024/1024);
    print "  segments:\n";
    foreach (@recs) {
      printf ("    %x-%x (%d bytes %.1f MB) %s %d\n",
	      $_->{start}, $_->{end}, $_->{size}, $_->{size}/1024/1024,
	      $_->{perms}, $_->{offset});
    }
  }
}
----------------------------------------------------------------------

-- 
Richard Jones
Red Hat