Re: Lets (not) break all the things. Was: [pgsql-advocacy] 9.6 -> 10.0

Bruce Momjian <bruce@momjian.us>

From: Bruce Momjian <bruce@momjian.us>
To: Jim Nasby <Jim.Nasby@BlueTreble.com>
Cc: "Joshua D. Drake" <jd@commandprompt.com>, Josh berkus <josh@agliodbs.com>, Robert Haas <robertmhaas@gmail.com>, Justin Clift <justin@postgresql.org>, Merlin Moncure <mmoncure@gmail.com>, PostgreSQL Hackers Mailing List <pgsql-hackers@postgresql.org>, Simon Riggs <simon@2ndquadrant.com>
Date: 2016-06-21T02:10:02Z
Lists: pgsql-hackers
On Tue, May 24, 2016 at 09:23:27AM -0500, Jim Nasby wrote:
> On 5/16/16 2:36 AM, Bruce Momjian wrote:
> >Right.  I am thinking of writing some docs about how to avoid downtime
> >for upgrades of various types.
> 
> If there's some magic sauce to shrink pg_upgrade downtime to near 0 I think
> folks would be very interested in that.
> 
> Outside of that scenario, I think what would be far more useful is
> information on how to do seamless master/replica switchovers using tools
> like pgBouncer or pgPool. That ability is useful *all* the time, not just
> when upgrading. It makes it trivial to do OS-level maintenance, and if
> you're using a form of logical replication it also makes it trivial to do
> expensive database maintenance, such as cluster/vacuum full/reindex. I've
> worked with a few clients that had that ability and it was a huge stress
> reducer. As a bonus, an unplanned outage of the master becomes far less
> stressful, because you already know exactly how to fail over.

pg_upgrade's runtime can't be decreased dramatically --- I wanted to
document other methods like you described.

-- 
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

+ As you are, so once was I. As I am, so you will be. +
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