> No it's not. You'll have to re-open connections to databases all the time. You can't use keep-alive to external HTTP APIs. You'll have to re-parse the PHP for every request.

What? This is all factually incorrect.

1) PHP has supported persistent database connections for ages. The fact is, persistent DB connections aren't really that great for websites, where you need a few resources quickly and then nothing for a long time. Having 10,000 idle DB connections is a great way to eat up resources. But you can do it.

2) PHP can use cURL's multi-handles, providing a per-application keep-alive connection pool (e.g. see Guzzle: http://guzzlephp.org/tour/http.html#managed-persistent-http-...).

3) While not part of PHP itself, most serious PHP applications use something like APC, which caches PHP opcodes to prevent constant reparsing.