Re: Synchronous Standalone Master Redoux

On Fri, Jul 13, 2012 at 12:25 AM, Amit Kapila <amit(dot)kapila(at)huawei(dot)com> wrote:
>
>> From: pgsql-hackers-owner(at)postgresql(dot)org
> [mailto:pgsql-hackers-owner(at)postgresql(dot)org]
>> On Behalf Of Jose Ildefonso Camargo Tolosa
>>>On Thu, Jul 12, 2012 at 9:28 AM, Aidan Van Dyk <aidan(at)highrise(dot)ca> wrote:
>> On Thu, Jul 12, 2012 at 9:21 AM, Shaun Thomas <sthomas(at)optionshouse(dot)com>
> wrote:
>>
>
>> As currently is, the point of: freezing the master because standby
>> dies is not good for all cases (and I dare say: for most cases), and
>> having to wait for pacemaker or other monitoring to note that, change
>> master config and reload... it will cause a service disruption! (for
>> several seconds, usually, ~30 seconds).
>
> Yes, this is true that it can cause service disruption, but the same will be
> True even if master detects that internally by having timeout.
> By keeping this as external, the current behavior of PostgreSQL can be
> maintained that
> if there is no standy in sync mode, it will wait and still serve the purpose
> as externally it can send message for master.
>

How does currently PostgreSQL detects that its main synchronous
standby went away and switch to another synchronous standby on the
synchronous_standby_names config parameter?

The same logic could be applied to "no more synchronous standbys: go
into standalone" (optionally).

--
Ildefonso Camargo
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