On Tue, May 12, 2015 at 07:27:22PM +0100, Howard Chu wrote:
Or, each session should be established completely sequentially - do a complete refresh from provider #1, then do the same for provider #2, etc... In a quiescent setup, the refreshes after provider #1 will be no-ops because the consumer is already up to date. In a busy setup, each refresh will still have work to do but it will be a smaller volume after provider #1's refresh completes.
Presumably the earlier connections would have entered persist state by then, so some of the changes could already have arrived.
Simplest would be to just establish the first connection and ignore other providers unless the first connection breaks. Unfortunately this wouldn't be reliable in MMR - you could have two nodes pointed at each other, ignoring any other nodes in the configuration.
That suggests that the consumer should attempt refresh from every supplier whenever it can establish a new connection, but that a preference order should be applied so that it does not try to refresh from a distant/slow provider first.