Are get_bloginfo queries cached to start, or should they be cached?

Question

I was just wondering if calling get_bloginfo too many times was going to harm performance in a theme and if the data should just be put into its own var?

Answer 1

get_bloginfo() is not cached and calling it over and over would harm your performance just like creating many calls to the database yourself.

a simple solution which doesn't evolve any caching in to minimize the database and function calls by defining a an array with all the info you need and save that as an option in the wp_options table.

then in your header.php globalize a variable and assign that option to it and every were in your them you can just use that, something like this:

in your functions.php

function set_get_my_blog_info(){
    $my_blog_info = get_option('my_blog_info');
    if ($my_blog_info === false){
        global $wp_version
        $lang = get_locale();
        $lang = str_replace('_', '-', $lang);
        $my_blog_info = array(
            'url' => home_url(),
            'wpurl' => site_url(),
            'description' => get_option('blogdescription'),
            'rdf_url' => get_feed_link('rdf'),
            'rss_url' => get_feed_link('rss'),
            'rss2_url' => get_feed_link('rss2'),
            'atom_url' => get_feed_link('atom'),
            'comments_atom_url' => get_feed_link('comments_atom'),
            'comments_rss2_url' => get_feed_link('comments_rss2'),
            'pingback_url' => get_option('siteurl') .'/xmlrpc.php',
            'stylesheet_url' => get_stylesheet_uri(),
            'stylesheet_directory' => get_stylesheet_directory_uri(),
            'template_url' => get_template_directory_uri(),
            'admin_email' => get_option('admin_email'),
            'html_type' => get_option('html_type'),
            'version' => $wp_version,
            'language' => $lang     
        );
        update_option('my_blog_info',$my_blog_info);
    }
    return $my_blog_info;
}

this will save most of the get_bloginfo options into one option in the database and will only run once.

then in your header.php add

global $my_blog_info;
$my_blog_info = set_get_my_blog_info();

and after you do that you can use that array anywhere you want in your theme, for example instead of:

echo get_bloginfo('url');

simply use your array:

echo $my_blog_options['url'];

Answer 2

While there is no inherent caching in get_bloginfo(), most of information it retrieves is from options and get_option() is cached.

Holding value you need in a variable for using several time is still (marginally in most cases) faster than function call, but I wouldn't bother with explicit dedicated caching.