How to tune a home web server on Ubuntu Server 15.04?

Question

ubuntu

I have a home web server running Ubuntu Server 15.04.
It has:
1) PHP 5.6.4
2) Apache 2.4.10
3) Redis 2.8.19
4) PostgreSQL 9.4.4
Nothing special was configured. Tell me how you can make a more flexible server configuration in order to increase security and improve system performance.

Answer 1

I would use 14.04.03 LTS.
15 has bugs when working out of the box.