php memory limit

function bytes_to_human($bytes) {
  $human = NULL;
    if ($bytes < 1024) {
      $human = number_format ($bytes, 0) .' bytes';
    } else if ($bytes < 1024*1024) {
      $human = number_format (($bytes / 1024), 1) . ' KB';
    } else {
      $human = number_format (($bytes / (1024*1024)), 1) . ' MB';
    }
  return $human;
}

if (function_exists ('memory_get_usage')) {
  $mem = memory_get_usage();
  $mem_text = bytes_to_human($mem);

  $rmem = memory_get_usage(TRUE);
  $rmem_text = bytes_to_human ($rmem);
  echo "Memory Usage: ". $mem_text ." / Real: ". $rmem_text ." :: ";
  unset ($mem, $mem_text, $rmem, $rmem_text);
}
if (function_exists('memory_get_peak_usage')) {
  echo "Peak Mem Usage: ";
  $mem = bytes_to_human(memory_get_peak_usage());
  $rmem = bytes_to_human(memory_get_peak_usage(TRUE));
  echo $mem ." / Real: ". $rmem;
}