php - Is there a faster/better way to check if an URL is reachable than cURL?

Solution:

As per comment, the cause of slowness isn't thecURL library. There's a whole system behind HTTP, such as DNS, web server(s), the connectivity to those servers and ultimately - every site / service uses some sort of server-side language to perform work, which can be slow as well. You need to find out what exactly in this chain isn't responding fast enough - is it DNS? Is it the connection of your server to the service you're connecting to? Is the service itself slow?

You can be 100% sure that it's notcURL.