I have high-load informative website with 10 000+ hits/day. It was rewritten on Symfony 2 Framework
with Doctrine2 ORM
. Site have heavy informative pages, each load on development server 0.5 - 1.5 seconds approximately. Note, that it time on development server, so it has minimal load.
I know there are many cache providers such as Varnish, Memcached, APC, HTTP, etc... Please, suggest me on what layer (DB, HTTP, etc...) and what type of cache better to use for improve performance of this site?