fixes #1317 remove cache directory size calculation

admin/include/functions.php

@@ -625,32 +625,6 @@ function get_fs_directories($path, $recursive = true)
   return $dirs;
 }
 
-/**
- * returns the size (in bytes) of a filesystem directory
- *
- * @since 11
- * @param string path
- * @return int
- */
-function get_fs_directory_size($path)
-{
-  $bytestotal = 0;
-  $path = realpath($path);
-
-  if (!function_exists('exec'))
-  {
-    return false;
-  }
-
-  @exec('du -sk '.$path, $returnarray);
-  if (is_array($returnarray) and !empty($returnarray[0]) and preg_match('/^(\d+)\s/', $returnarray[0], $matches))
-  {
-    $bytestotal = $matches[1] * 1024;
-  }
-
-  return $bytestotal;
-}
-
 /**
  * save the rank depending on given categories order
  *