On Sun, Oct 15, 2006 at 02:42:04PM -0400, Bill Moran wrote:
> transactions behind.  When the backlog got to 50, the master would block
> on new transactions until the slaves caught up.

[. . .]

> I don't know how difficult this would be to implement, it's just a
> thought.

I suppose you could do it by taking an exclusive lock (well, probably
a write lock would be enough) on every database object; the Slony
user already has to be a superuser, so it would have the permissions
necessary.  It'd have to be somewhat fuzzy (because you can't control
the transactions that perform BEGIN before you try to take your
lock), but it'd work.  I really question, though, whether it'd be a
good idea: the whole point of async replication is that what happens
on the replica doesn't affect transactions on the origin.  Wouldn't
two-phase commit be better for this?

A

-- 
Andrew Sullivan  | ajs at crankycanuck.ca
This work was visionary and imaginative, and goes to show that visionary
and imaginative work need not end up well. 
		--Dennis Ritchie