pg.ddx.io  pgsql-admin@postgresql.org mailing list archive  
help / color / mirror / Atom feed
From: Wim Bertels <wim.bertels@ucll.be>
To: Keith Fiske <keith.fiske@crunchydata.com>
Cc: pgsql-admin <pgsql-admin@postgresql.org>
Subject: Re: viewing connectioninfo used by subscriber on the publication server when inactive
Date: Thu, 14 May 2020 16:22:27 +0200
Message-ID: <95bb0c6c21a2a96a526a5ce01f16e62ea4f073f5.camel@ucll.be> (raw)
In-Reply-To: <CAODZiv5J2op7t5_P-6gQwKXVefmFXV9WhLPtN159U_PbyyM_jQ@mail.gmail.com>
References: <25037dc66dadcdd61148f6d59208217441abfd80.camel@ucll.be>
	<CAODZiv5QMzAd5_ckxMMfxv84Y3YeASX9ePF3k1u1ERnRKgmrEw@mail.gmail.com>
	<5f77a6c973aaf8f9086cf42933f476e5bd9a948d.camel@ucll.be>
	<CAODZiv4LpJ+RfkfesjC91w446hjA3Hhsk_9-TG=cVO8h-0ihLQ@mail.gmail.com>
	<562890eff48a048d4b09d23f76506fceb867a31f.camel@ucll.be>
	<CAODZiv5J2op7t5_P-6gQwKXVefmFXV9WhLPtN159U_PbyyM_jQ@mail.gmail.com>

Keith Fiske schreef op do 14-05-2020 om 10:08 [-0400]:
> It doesn't matter how small the dataset change is. The same WAL
> stream is used for both logical and physical replication so it has to
> keep all WAL files until all subscribers for that publication have
> confirmed they have received them. If even a single subscriber goes
> offline, all WAL will be kept until that subscriber reconnects.

That is interesting, i assume this the WAL for the whole cluster, as
logical decoding is then used on this WAL for the logical replication,
do you have an estimate of order of magnitude for the all WAL files?

So far this seems ok over here (with one subscriber inactive for 2
days):
# du -ch pg_logical/ pg_wal/ pg_replslot/
912K	pg_logical/snapshots
4,0K	pg_logical/mappings
924K	pg_logical/
4,0K	pg_wal/archive_status
81M	pg_wal/
8,0K	pg_replslot/db2_sub
8,0K	pg_replslot/db2_sub1
8,0K	pg_replslot/db2_sub2
28K	pg_replslot/
81M	totaal
this after two days of replication setup. 

assuming that students will be offline for at most 2 or 3 days,
this seems ok?

-- 
mvg,
Wim
--
Tell the truth or trump--but get the trick.
		-- Mark Twain, "Pudd'nhead Wilson's Calendar"






view thread (12+ messages)  latest in thread

Message-ID: <95bb0c6c21a2a96a526a5ce01f16e62ea4f073f5.camel@ucll.be>
Permalink:  ../95bb0c6c21a2a96a526a5ce01f16e62ea4f073f5.camel@ucll.be/
Also on:    postgresql.org/message-id/95bb0c6c21a2a96a526a5ce01f16e62ea4f073f5.camel@ucll.be

 · 

reply

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-admin@postgresql.org
  Cc: wim.bertels@ucll.be, keith.fiske@crunchydata.com
  Subject: Re: viewing connectioninfo used by subscriber on the publication server when inactive
  In-Reply-To: <95bb0c6c21a2a96a526a5ce01f16e62ea4f073f5.camel@ucll.be>

* 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