Re: Sending notifications from the master to the standby

Simon Riggs <simon@2ndquadrant.com>

From: Simon Riggs <simon@2ndQuadrant.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Josh Berkus <josh@agliodbs.com>, pgsql-hackers@postgresql.org
Date: 2012-01-12T15:18:46Z
Lists: pgsql-hackers
On Wed, Jan 11, 2012 at 11:38 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:

>> The obvious first use case for this is for cache invalidation.
>
> Yeah, upthread Simon pointed out that propagating notifies would be
> useful for flushing caches in applications that watch the database in a
> read-only fashion.  I grant that such a use-case is technically possible
> within the limitations of a slave server; I'm just dubious that it's a
> sufficiently attractive use-case to justify the complexity and future
> maintenance costs of the sort of designs we are talking about.  Or in
> other words: so far, cache invalidation is not the "first" use-case,
> it's the ONLY POSSIBLE use-case.  That's not useful enough.

Many people clearly do think this is useful.

I personally don't think it will be that complex. I'm willing to
review and maintain it if the patch works the way we want it to.

-- 
 Simon Riggs                   http://www.2ndQuadrant.com/
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