Quote:

there are still several Big Fat Reasons™ to use DIY replicas

Another Quote:

With the Replication Messages described above, it is ok to apply Replication Messages to Slave DB which is newer than exactly necessary.

Quote:

if we can commit several transactions at the same time – RDBMS needs to fsync() our DB logs to physical disks only once

Another Quote:

if going our preferred way of single-writing-DB connection – make sure NOT to use RDBMS-level Group Commit

Quote:

with our app-level cache, we’re guaranteed to get exactly the same results as if we’d be querying the underlying database.

Another Quote:

why settle for invalidation when we can modify cache accordingly, saving on the extra DB request when we’re dealing with the same USER again?

Quote:

Have I already mentioned that you DO need to understand execution plans?

Another Quote:

DO keep in mind that maintaining indexes has its own cost