sub foo {
  my $resourceHandle = acquire_locked_resource();
  my $dbh = get_database_handle;
  my $count = get_current_users($dbh);
  my $elapsed = get_elapsed_time();

  my $users_per_second = $count/$elapsed;

  $resourceHandle->output("$users_per_second users/s");

  $resourceHandle->release;
};