Re: Standalone synchronous master

Robert Haas <robertmhaas@gmail.com>

From: Robert Haas <robertmhaas@gmail.com>

To: Aidan Van Dyk <aidan@highrise.ca>

Cc: Alexander Björnhagen <alex.bjornhagen@gmail.com>, Magnus Hagander <magnus@hagander.net>, Fujii Masao <masao.fujii@gmail.com>, pgsql-hackers@postgresql.org

Date: 2012-01-04T18:04:26Z

Lists: pgsql-hackers

On Wed, Jan 4, 2012 at 9:28 AM, Aidan Van Dyk <aidan@highrise.ca> wrote:
> I'ld love a "hook" script that was run if sync-rep state ever changed
> (heck, I'ld even like it if it just choose a new sync standby).

That seems useful.  I don't think the current code quite knows its own
state; we seem to have each walsender recompute who the boss is, and
if you query pg_stat_replication that redoes the same calculation.  I
can't shake the feeling that there's a better way... which would also
facilitate this.

> Even better, is there a way we could start injecting "notify" events
> into the cluster on these types of changes?  Especially now that
> notify events can take payloads, it means I don't have to keep
> constantly polling the database to see if it things its connected,
> etc.

I like this idea, too.

-- 
Robert Haas
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