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 1mpwDk-0005Or-2a for pgsql-admin@arkaria.postgresql.org; Wed, 24 Nov 2021 17:38:12 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.92) (envelope-from ) id 1mpwDi-0008JK-IQ for pgsql-admin@arkaria.postgresql.org; Wed, 24 Nov 2021 17:38:10 +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 1mpwDi-0008JB-7n; Wed, 24 Nov 2021 17:38:10 +0000 Received: from mout.perfora.net ([74.208.4.197]) by makus.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1mpwDg-0000Cr-0m; Wed, 24 Nov 2021 17:38:09 +0000 Received: from [192.168.1.167] ([98.169.214.209]) by mrelay.perfora.net (mreueus003 [74.208.5.2]) with ESMTPSA (Nemesis) id 0MHVog-1mmdMd1ed2-003Nw5; Wed, 24 Nov 2021 18:38:03 +0100 Subject: Re: Re: To: Holger Jakobs Cc: pgsql-admin@lists.postgresql.org, Simon Riggs , Firthouse banu , pgsql-admin References: <6cb32d43-75d1-b896-5267-48d75c536808@sqlexec.com> <0ED6B91F-C228-404F-A4F2-B9532E205B2D@jakobs.com> From: MichaelDBA Message-ID: <7713c1fd-c674-eb79-02ea-0daf749ac098@sqlexec.com> Date: Wed, 24 Nov 2021 12:38:00 -0500 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 PostboxApp/7.0.52 MIME-Version: 1.0 In-Reply-To: <0ED6B91F-C228-404F-A4F2-B9532E205B2D@jakobs.com> Content-Type: multipart/alternative; boundary="------------183B12E09FD2DB4E38D3E406" Content-Language: en-US X-Provags-ID: V03:K1:RoVG9ajXB1jqto4nCQsTCKOMnC4GcFNWqOcB3jyxhB8ZD2vfsuz cuHwlAOTayr+/w5UvTY1jVbOfd5b6/Wsb4VCGfzxL7cvuFxXcKZ4gvfB2hMkSM+hTBEAZri 5j7fE/t+XFsLZtnmQu6AclPFNgIBsB/AfnQqbkRq3feZbsE1ULC6PA74rBbo6JEFKurd292 tDDMqtNmm5pmXsNuYxWEg== X-Spam-Flag: NO X-UI-Out-Filterresults: notjunk:1;V03:K0:Nzka6UpaX0E=:HssRvJ3xrbxY8dHfGa2hiS JwCoFXiMWpvGgdTUEFetXzFRCk5EoogLls5rUpLy5ChSAr+ussgihlVuVt5d6mOnnoQr6mavU R7SbkvVk6kjtedq5eOfKqKCCoc3o7q2kqQYzB6jeFEjwldL0wiDD3Xruf71FDDWVUrtYoWkAy RyKt7VmsC3JQ1NZb+OgEPbk1o0FdMLzNOJVCG4EvhLGFYn8VFik32/jvO760qLodT74i4gbJD 50aCq/GijfRz9id/3tB3fqfgNB5WS68tGuZn3qGvdoEc6T8/bvgxhQwwDZlqTJX6cqsq7cX8b NRop6RJACJBy7/vaH+aAIFsC6nKsUR4Dwga6Jm8ZyTJEJDHAes1+wzyfzqlUz/zxonLz0EFIq UW+rMm9IrDRkr3ucOSu58RG/VAU4LTzjawEbL7BUAP/0q+YVLt8BneAJmn+kuEoG+il3PPwQI WbHRxOO/FkMwZ0QGze9ZgvJoHAyT8JOc6qFepqNk9rNeK0B8StEAAq2g3SIbuImIIy6v6/xIM AI/6xwOj2EmjHayo8/pJepMbQRAqs1bBhW2N99Lwmzy8CzhczbHgkDjsgZmWj8J4ZWlp1T+el yWu5UrktIzDi7BnI9cozG/L3OcqMD0npEYS0Q35jRuF4EfSu3pymnB0xZbyyuZfOmzUNUrBul tq+T6PNZKkGXoUhgyeq15lh5bFxdOhl5x7P4W11TaUf1lcHb4J3E5gq6INcE7tlIBfYfTzI3X 6/QIQNdTBCSlo76o List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk This is a multi-part message in MIME format. --------------183B12E09FD2DB4E38D3E406 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Oh really? BDR is acid-compliant? How can it be without a global lock manager to control access to resources and a consistent view of data and enforce isolation levels? Please explain the magic. On Wed, 24 Nov 2021 at 14:03, MichaelDBA wrote: > You do understand that multi-master replication is not acid-compliant > and the implications of that, right? It only works well for "read > globally, write locally" scenarios. This isn't true. Async multi-master has performance advantages, but some drawbacks. But systems such as BDR3 allow multiple modes of operation that overcome these perceived issues. Holger Jakobs wrote on 11/24/2021 12:08 PM: > On Wed, 24 Nov 2021 at 14:03, MichaelDBA wrote: >> You do understand that multi-master replication is not acid-compliant >> and the implications of that, right? It only works well for "read >> globally, write locally" scenarios. > This isn't true. > > Async multi-master has performance advantages, but some drawbacks. But > systems such as BDR3 allow multiple modes of operation that overcome > these perceived issues. --------------183B12E09FD2DB4E38D3E406 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 7bit 
Oh really?  BDR is acid-compliant? How can it be without a global lock manager to control access to resources and a consistent view of data and enforce isolation levels?

Please explain the magic.


On Wed, 24 Nov 2021 at 14:03, MichaelDBA <MichaelDBA@sqlexec.com> wrote:

You do understand that multi-master replication is not acid-compliant
and the implications of that, right? It only works well for "read
globally, write locally" scenarios.

This isn't true.

Async multi-master has performance advantages, but some drawbacks. But
systems such as BDR3 allow multiple modes of operation that overcome
these perceived issues.


Holger Jakobs wrote on 11/24/2021 12:08 PM:
On Wed, 24 Nov 2021 at 14:03, MichaelDBA <MichaelDBA@sqlexec.com> wrote:

You do understand that multi-master replication is not acid-compliant
and the implications of that, right? It only works well for "read
globally, write locally" scenarios.

This isn't true.

Async multi-master has performance advantages, but some drawbacks. But
systems such as BDR3 allow multiple modes of operation that overcome
these perceived issues.

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