On Wed, 2009-01-28 at 14:56 -0500, Tom Lane wrote:
> Well, those unexpectedly cancelled queries could have represented
> critical functionality too. I think this argument calls the entire
> approach into question. If there is no safe setting for the parameter
> then we need to find a way to not have the parameter.
I see the opposite: We don't know what tradeoffs, if any, the user is
willing to put up with, so we need input. It is about resource
prioritisation and not for us to decide, since these reflect business
objectives not internal twangy things like join_collapse_limit.
The essential choice is "What would you like the max failover time to
be?". Some users want one server with max 5 mins behind, some want two
servers, one with 0 seconds behind, one with 12 hours behind
-- Simon Riggs www.2ndQuadrant.comPostgreSQL Training, Services and Support