For some reason W3TC cache preload didn’t work, the w3_pgcache_prime was set, but the cron event was still missing.
While the web hosting didn’t allow CLI like cron to schedule php wp-cli.phar w3-total-cache pgcache_prime I ended up by reusing the command PHP code in a new file which is called via cron.
<?php
/**
* Web version of:
* php wp-cli.phar w3-total-cache pgcache_prime
*
* Check W3TC cache prime offset
* SELECT * FROM `md_options` WHERE `option_name` = 'w3tc_pgcache_prime_offset';
*/
use W3TC\Dispatcher;
error_reporting( -1 );
require_once __DIR__ . '/../wp-load.php';
try {
$o = Dispatcher::component( 'PgCache_Plugin_Admin' );
$o->prime(
( isset( $vars['start'] ) ? $vars['start'] - 1 : null ),
( $vars['limit'] ?? null )
);
} catch ( \Exception $e ) {
error_log( __( 'PageCache Priming did failed: %s', 'w3-total-cache' ), $e );
}
error_log( __( 'PageCache Priming triggered successfully.', 'w3-total-cache' ) );
Mikha'el's Blog 