add to functions.php : optimize wordpress heartbeat settings for admin pages

optimize_heartbeat.php

<?php
// as include for functions.php
function optimize_heartbeat_settings( $settings ) {
    $settings['autostart'] = false;
    $settings['interval'] = 60;
    return $settings;
}
add_filter( 'heartbeat_settings', 'optimize_heartbeat_settings' );

function disable_heartbeat_unless_post_edit_screen() {
    global $pagenow;
    if ( $pagenow != 'post.php' && $pagenow != 'post-new.php' )
        wp_deregister_script('heartbeat');
}
add_action( 'init', 'disable_heartbeat_unless_post_edit_screen', 1 );

// end heartbeat