This is very smart! I am curious about how they implemented this. I wonder if by "replication stream" they are just referring to binary logs. The article didn't mention whether they hacked MySQL to do synchronous replication as well, like Google. That would be really neat: synchronous replication that updates memcached.
Synchronous or not, the idea is still uber cool and I would love to see more discussion from Planet MySQL community regarding this.
Making replication possible for Brian Aker's memcached storage engine for MySQL can be another way in the future to making MySQL replicate to memcached. Brian's blog post shows:
ENGINE=MEMCACHE DEFAULT CHARSET=latin1 CONNECTION='localhost,piggy,bitters'The multiple host specification looks very interesting. I will definitely love to talk about this with the brains at the conference.
Also, something like this would make a nice candidate for programs like Google summer of code.
Thanks to my colleague and friend A. Lee for brining this to my attention.