Are persistent connections needed with php5-fpm?

Question

PHP

Outside nginx, inside php5-fpm, socket connection.
The upstream directive can contain the keepalive option .
Does it make any sense to use it and is it supported?

Answer 1

No, it doesn't make sense at all.
Moreover, it's a bit harmful - disabling keepalive allows php-fpm to kill unnecessary threads (and free up memory), instead of leaving them (because they keep it like keepalive). True, fpm must be able to keep keepalive by the master process (more precisely, "transfer" such connections to the master process over time). The only question is whether fpm has learned how to do it correctly =)
With the Apache behind keepalive, you definitely need to turn it off.