WP Smush.it Timeout

WP Smush.it’s default timeout is set at 25 seconds. If you constantly experience timeout errors, you can increase it by modifying wp-smushit.php file.

Locate:

/**
* http_request_timeout filter — bumped up to 25 seconds for larger images
*/
function wp_smushit_http_request_timeout($time) {
return 25;
}

You can increase the timeout from 25 to a bigger value.