[bobobjorn]

I assume this has the effect that memcached is always full. How do you know when the hot cache is starting to fill memcached? Ie, how do you know when your cache memory is closing up to beeing to small?

[ars]

You probably calculate the ratio of hot requests vs cold ones. Or in other words, the cache miss ratio.

[bobobjorn]

But that wont show anything until it most likely already is to late. You dont realy want that value to ever go down, then you already have customers with a worse experience, and when that starts, it goes very fast down the hill.