I've been thinking about what changes we may have to make to our memcached installation in future as we continue to grow - our webfarm is approaching 100 servers, each with 4GB ram, ~2GB of which is dedicated to memcached on each machine.
As we add more nodes, the usefulness of get_multi decreases - it's possible for a single page to hit almost all of the memcached instances. I read somewhere that facebook partition their memcached cluster to improve get_multi performance (eg, all user data on a subset of mc nodes). Can anyone comment on the effectiveness of this? Are we fighting a losing battle here - perhaps we should try and cram as much ram as possible into a small number of machines (what do you do?). get_multi would be more useful, but it costs more and doesn't seem as elegant :( Can anyone comment on how many memcache lookups they make per page? Traditionally our developers treated memcache lookups as "free", but when you're doing a few hundred memcache gets per page it soon adds up.. Thanks, RJ -- Richard Jones Last.fm Ltd. | http://www.last.fm/ Office: +44 (0) 207 780 7080
