Re: Core team statement on replication in PostgreSQL - Mailing list pgsql-hackers

On Thu, 2008-05-29 at 09:18 -0700, Josh Berkus wrote:
> Bruce,
> 
> > Another idea I discussed with Tom is having the slave _delay_ applying
> > WAL files until all slave snapshots are ready.
> > 
> 
> Well, again, that only works for async mode.

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"?

With this type of replication there will always be a difference for some
small window, but most people would expect that window to be very small
for synchronous replication.

Regards,Jeff Davis