_prime_comment_caches() WP 4.4.0

Adds any comments from the given IDs to the cache that do not already exist in cache.

No Hooks.

Return

Nothing (null).

Usage

_prime_comment_caches( $comment_ids, $update_meta_cache );

$comment_ids(array) (required)

Array of comment IDs.

$update_meta_cache(true/false)

Whether to update the meta cache.
Default: true

Code of prime comment caches: wp-includes/comment.php ^{VER 5.0.3}

<?php
function _prime_comment_caches( $comment_ids, $update_meta_cache = true ) {
	global $wpdb;

	$non_cached_ids = _get_non_cached_ids( $comment_ids, 'comment' );
	if ( !empty( $non_cached_ids ) ) {
		$fresh_comments = $wpdb->get_results( sprintf( "SELECT $wpdb->comments.* FROM $wpdb->comments WHERE comment_ID IN (%s)", join( ",", array_map( 'intval', $non_cached_ids ) ) ) );

		update_comment_cache( $fresh_comments, $update_meta_cache );
	}
}