Re: standby registration (was: is sync rep stalled?)

On Thu, Oct 7, 2010 at 2:33 PM, Josh Berkus <josh(at)agliodbs(dot)com> wrote:
>> I think they work together fine.  Greg's idea is that you list the
>> important standbys, and a synchronization guarantee that you'd like to
>> have for at least one of them.  Simon's idea - at least at 10,000 feet
>> - is that you can take a pass on that guarantee for transactions that
>> don't need it.  I don't see why you can't have both.
>
> So, two things:
>
> 1) This version of Standby Registration seems to add One More Damn Place
> You Need To Configure Standby (OMDPYNTCS) without adding any
> functionality you couldn't get *without* having a list on the master.
> Can someone explain to me what functionality is added by this approach
> vs. not having a list on the master at all?

Well, then you couldn't have one strictly synchronous standby and one
asynchronous standby.

> 2) I see Simon's approach where you can designate not just synch/asynch,
> but synch *mode* per session to be valuable.  I can imagine having
> transactions I just want to "ack" vs. transactions I want to "apply"
> according to application logic (e.g. customer personal information vs.
> financial transactions).  This approach would still seem to remove that
> functionality.  Does it?

I'm not totally sure. I think we could probably avoid removing that
with careful detailed design.

--
Robert Haas
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