# Returns
#  (vsize, rss, shared pages, code pages, data+stack pages)
# in kilobytes.  Precision is to nearest 4k page.
# TODO: Proc::ProcessTable so that we can support non-Linux?
my $page_size_in_kb = 4;
sub _get_mem_data
{
	my ($class, $pid) = @_;

	sysopen(my $fh, "/proc/$pid/statm", 0) or die $!;
	sysread($fh, my $line, 255) or die $!;