> But which client? Usually if you need memcache to scale you will be > running many clients in parallel - and if they are doing single-key > operations in many cases adding more servers will make them completely > separate. It is only multi-gets with many small keys that don't > scale forever.
If you enable persistent conns, you'll build up tons of connections (one per memd per client process). If you don't use persistent conns, but access memcached several times during a request, the odds of having to do a 3-way handshake before every request increases. > Yes, it is more a matter of using smart clients. But still, you are > likely to have a problem with your backend persistent storage before > you get to that point - especially if you expect to recover from any > major failure that dumps most of your cache at once. Yes :) Reality trumps most of these issues in a few ways; keeping up with your backing store is one. Another decent reality is that if you have an installation that large, odds are you can afford specialists who can ensure it continues to work.
