Wo würde ich hier $files cachen?

gistfile1.txt

# Model

class S3_File {
  public function get_all_files(){
    # code getting object of s3_files as $files
    return $files;
  }
}

# Controller

class File_Controller {
  public function action_files(){
    $s3files = new S3_File();
    $files = $s3files->get_all_files();
    render('site');
  }
}