On Fri, Jan 10, 2014 at 2:33 PM, Andres Freund <and...@2ndquadrant.com>wrote:
> On 2014-01-10 14:29:58 -0800, Joshua D. Drake wrote: > > db02 goes down. It doesn't matter why. It is down. db01 continues to > accept > > orders, allow people to log into the website and we can still service > > accounts. The continuity of service continues. > > Why is that configuration advantageous over a async configuration is the > question. Because it is orders of magnitude less likely to lose transactions that were reported to have been committed. A permanent failure of the master is almost guaranteed to lose transactions with async. With auto-degrade, a permanent failure of the master only loses reported-committed transactions if it co-occurs with a temporary failure of the replica or the network, lasting longer than the time out period. Why, with those requirements, are you using a synchronous > standby at all? > They aren't using synchronous standby, they are using asynchronous standby because we fail to provide the choice they prefer, which is a compromise between the two. Cheers, Jeff
