How to grow

load sharing or load balancing? simple or complex?

[starec]

I currently have one server serving dynamic pages (php) behind another machine that acts as caching server.

This setup has reached its limits and the only way out is seems to be to add another machine.

I want to change the architecture to make the system scalable because I hope to grow further:)

I am wondering which way to go: some simple (round robin or mod-rewrite) load sharing, or some more complex solution, like linux virtual server?

My knowledge in this area is very limited and i feel a bit lost...

[sun818]

Is the load coming from your PHP scripts being processed? Calls to the database? Can parts of your site become static?

[starec]

The load is coming from php (Well, some part of it would be MySQL calls, but the bottleneck is php). The php code is optimized for speed.

All pages that can be static are static, all dynamic pages that do not change very often are cached by a squid server.

While there still might be some things to do to boost the performance of the current system, it is clear that very soon a new machine will have to be added, and I would like to know how what is the best way of doing it.