From: Bruce Momjian <bruce@momjian.us>
To: Fabio Pardi <f.pardi@portavita.eu>
Cc: pgsql-performance@lists.postgresql.org
Subject: Re: Fwd: upgrade to PG11 on secondary fails (no initdb was launched)
Date: Fri, 14 Jun 2019 10:44:09 -0400
Message-ID: <20190614144409.bmrlzgnu4ibhz2cr@momjian.us> (raw)
In-Reply-To: <20190614143940.vux2quolie4s6luv@momjian.us>
References: <CA+t6e1nixp7tqTS3m1tV+XxC45gL8XG6JtSt5QdLYwBTCW3WmA@mail.gmail.com>
<CA+t6e1k-xEkjhUTnLik8MCf7-Sb+ek71jsZVN0ewduLEBy0iPw@mail.gmail.com>
<68cf5e6c-8eb0-d8dc-08ec-78d8e910c17c@portavita.eu>
<20190614033001.5jif725fxchtopg7@momjian.us>
<b07e8a66-b122-8f41-03b3-6d2fc236f3e7@portavita.eu>
<20190614143940.vux2quolie4s6luv@momjian.us>
On Fri, Jun 14, 2019 at 10:39:40AM -0400, Bruce Momjian wrote:
> On Fri, Jun 14, 2019 at 03:12:29PM +0200, Fabio Pardi wrote:
> > Using --size-only, tells rsync to only check the size of the blocks.
> > That is: if the block is present on the destination, and is the same
> > size as the origin, then skip.
>
> The files are _exactly_ the same on primary and standby, so we don't
> need to check anything. Frankly, it is really only doing hard linking
> of the files.
Here is the description from our docs:
What this does is to record the links created by pg_upgrade's
link mode that connect files in the old and new clusters on the
primary server. It then finds matching files in the standby's old
cluster and creates links for them in the standby's new cluster.
Files that were not linked on the primary are copied from the
primary to the standby. (They are usually small.) This provides
rapid standby upgrades. Unfortunately, rsync needlessly copies
files associated with temporary and unlogged tables because these
files don't normally exist on standby servers.
The primary and standby have to be binary the same or WAL replay would
not work on the standby. (Yes, I sometimes forgot how this worked so I
wrote it down in the docs.) :-)
--
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. +
+ Ancient Roman grave inscription +
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-performance@postgresql.org
Cc: bruce@momjian.us, f.pardi@portavita.eu, pgsql-performance@lists.postgresql.org
Subject: Re: Fwd: upgrade to PG11 on secondary fails (no initdb was launched)
In-Reply-To: <20190614144409.bmrlzgnu4ibhz2cr@momjian.us>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox