wp-setting php memory problems

I have been struggling with overloaded server memory issues. I have been reading up on wp-config and wp-settings regarding memory and wonder if I may have found a problem.

In the wp-config tutorial, it says that the php memory settings will be listed near the top of the code. As you can see below, there are no settings, just a line prompting to set the memory limits.

Is there a line missing?

* @since 1.0.0
 */
define( 'WPINC', 'wp-includes' );

// Include files required for initialization.
require( ABSPATH . WPINC . '/load.php' );
require( ABSPATH . WPINC . '/default-constants.php' );

/*
 * These can't be directly globalized in version.php. When updating,
 * we're including version.php from another install and don't want
 * these values to be overridden if already set.
 */
global $wp_version, $wp_db_version, $tinymce_version, $required_php_version, $required_mysql_version;
require( ABSPATH . WPINC . '/version.php' );

// Set initial default constants including WP_MEMORY_LIMIT, WP_MAX_MEMORY_LIMIT, WP_DEBUG, WP_CONTENT_DIR and WP_CACHE.
wp_initial_constants();

// Check for the required PHP version and for the MySQL extension or a database drop-in.
wp_check_php_mysql_versions();

// Disable magic quotes at runtime. Magic quotes are added using wpdb later in wp-settings.php.
@ini_set( 'magic_quotes_runtime', 0 );
@ini_set( 'magic_quotes_sybase',  0 );

[Moderator Note: Please post code & markup between backticks or use the code button. Your posted code may now have been damaged by the forum’s parser.]