From 11 months ago: [http://programming.reddit.com/info/jl2a/comments/cjpfw http://programming.reddit.com/info/jl2a/comments/cjpfw] " We use postgresql + slony

From 11 months ago: [http://programming.reddit.com/info/jl2a/comments/cjpfw http://programming.reddit.com/info/jl2a/comments/cjpfw] " We use postgresql + slony, and are fairly pleased. Most of the time reddit slows down, it's db related, but so far there has always been a way to work through it. That being said, I feel we have to spend far too much time worrying about the database, and that's probably the situation with any relational db. Presently, we have a db master that replicated to one machine, and that second machine replicates to a couple others. Most of the reddit queries are handled by the master and the first slave. The other slaves are used for backups and slow queries (e.g. stats and recommendations). Replication and query load-balancing helped out a lot with the database load, but it introduced a new host of problems. Replication lag, in particular. This occurs when a db write is committed to the master, but the next read hits a slave before the write has propagated. "