David Fetter wrote:
> Either one of these would be great, but something that involves
> machines that stay useless most of the time is just not going to work.
Lots of people do use warm standby already anyway, just not based on
mechanisms built into PostgreSQL. So defining away this need is completely
unrealistic based on my experience. Even if there were a read-only slave,
lots of applications couldn't make use of it.
Anyway, a common approach to making better use of the hardware is to put some
other service on the otherwise-standby machine, which in turn uses your
master database server machine as its failover target. Unless you run *only*
a database, there would usually be some candidate that you could set up that
way.
Another common approach is to realize that for some the costs of a downtime
risk are higher than buying some extra hardware.
I think the consensus in the core team was that having synchronous log
shipping in 8.4 would already be a worthwhile feature by itself.