Caching paginated results, purging on update - how to solve?

Question

I\'ve created a forum, and we\'re implementing an apc and memcache caching solution to save the database some work.

I started implementing the cache layer with keys like

Answer 1

Be very careful about doing this kind of optimisation without having hard facts to measure against.

Most databases have several levels of caches. If these are tuned correctly, the database will probably do a much better job at caching, than you can do your self.