Re: Core team statement on replication in PostgreSQL

Jeff Davis wrote:
> It depends on what we mean by synchronous. Do we mean "the WAL record
> has made it to the disk on the slave system," or "the WAL record has
> been applied on the slave system"?

DRBD, which is a common warm standby solution for PostgreSQL at the moment, 
provides various levels of synchronicity.  I imagine we could also define, as 
need arises, various levels, some of which may be the ones you listed.