Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1ltuut-0002Ou-A9 for pgsql-admin@arkaria.postgresql.org; Thu, 17 Jun 2021 16:30:55 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.92) (envelope-from ) id 1ltuus-0007GJ-8i for pgsql-admin@arkaria.postgresql.org; Thu, 17 Jun 2021 16:30:54 +0000 Received: from makus.postgresql.org ([2001:4800:3e1:1::229]) by malur.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1ltuur-0007GA-Vl for pgsql-admin@lists.postgresql.org; Thu, 17 Jun 2021 16:30:53 +0000 Received: from tamriel.snowman.net ([70.109.60.50]) by makus.postgresql.org with esmtp (Exim 4.92) (envelope-from ) id 1ltuup-0004ls-Sm for pgsql-admin@postgresql.org; Thu, 17 Jun 2021 16:30:52 +0000 Received: by tamriel.snowman.net (Postfix, from userid 1000) id 2A03E5F799; Thu, 17 Jun 2021 12:30:48 -0400 (EDT) Date: Thu, 17 Jun 2021 12:30:48 -0400 From: Stephen Frost To: LEROY TENNISON Cc: pgsql-admin Subject: Re: compression in replication Message-ID: <20210617163047.GM20766@tamriel.snowman.net> References: <1ltQeA-000URA-EE@unimaticaspa.it> <192101066.1663055.1623871300493@mail.yahoo.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="a+XlyCz8hkeSG9dV" Content-Disposition: inline In-Reply-To: <192101066.1663055.1623871300493@mail.yahoo.com> User-Agent: Mutt/1.5.24 (2015-08-30) List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk --a+XlyCz8hkeSG9dV Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Greetings, We generally prefer to do in-line replies (not top-posting) on these lists. So, more below. * LEROY TENNISON (leroy_tennison@prodigy.net) wrote: > Keep in mind that this can be accomplished in other ways depending on wh= at archive_command you're using.=A0 rsync, and sftp (I don't recommend scp = due to security concerns but it does compression as well) both have paramet= ers to do in-transit compression.=A0 If i remember correctly Postgresql com= pression must be enabled on both ends.=A0 I had a situation where that wasn= 't easy to do and opted for external (to Postgresql) compression. In general, rsync, sftp, and scp are very poor choices for archive command as they don't do anything to ensure that the WAL is actually written out to disk and also don't do a variety of other sensible checks to make sure the WAL matches the PG database, there's a history file for the timeline the WAL is on, etc. Thanks, Stephen --a+XlyCz8hkeSG9dV Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBCgAGBQJgy3i3AAoJEO1sijiDR2RVAXIP/1WTlnPQUPc8NND5qaUA0T6P 28+GAN1O+2REBthLRXEtU/rmzstNr77mAeUc0L1zTPxbvhurP5/0Boue3nywl9XY fyTEabdofqteVjxSO6LLypsMjNMwz2+gMVBiEmZE5yZDrZCPZ2wnFi8vUt5slEjb 2SO9ffPsfgGg4HEK9uaCGM4756vgweWU4NBXbzSecyZOPxaS10ipwJUb6wKju1Yp CuQ5SXzZaQCe+rqXaLvuDmwaeRdMUCFliRGi79WxB6hC2v9+Ta1b3zPxVAlHzMLx A0bOwGOIE+bjPbDS6xmNIUbKdkr/V+keeN9K0cDekCtktfMfex8w6O5q8uO+tcn5 nKF5+bC7LLyd2polMwohYDSLVbAfPkcwxX9IlfFVzgR6vROi+q/IiWbfnWoTF4G/ NtWPqDg7RUmbzmYxX4ZgxqjzUkfqoFOvkrKXLyzwPt7tqkrsdODf7ZSlI2hpAJA8 N8OYstnR8b+g41WJ703A8bqTLozAk+JWrzPJaiJT5SzKVe1gVZxgrc4K0555uD5U Qx3n3tiebjERmP6nvQR7SmApo2eAPuh81IG9IBMB6s+AreYe1/yDK8yncoInhUEj Q7ime5LfCA7pQpejzfxTbqftQPWNu1Nce1sdOlP9NxYPfZ1f1uwDi2i/kjIAqcAk wz8Zx+DOS3FYmbdwBebe =IgMN -----END PGP SIGNATURE----- --a+XlyCz8hkeSG9dV--