Re: Standalone synchronous master
Jim C. Nasby <jim@nasby.net>
From: Jim Nasby <jim@nasby.net>
To: "Joshua D. Drake" <jd@commandprompt.com>,
Bruce Momjian <bruce@momjian.us>, Amit Kapila <amit.kapila16@gmail.com>
Cc: Hannu Krosing <hannu@2ndquadrant.com>, MauMau <maumau307@gmail.com>,
Andres Freund <andres@2ndquadrant.com>,
Tom Lane <tgl@sss.pgh.pa.us>, Kevin Grittner <kgrittn@ymail.com>,
Heikki Linnakangas <hlinnakangas@vmware.com>,
Simon Riggs <simon@2ndquadrant.com>,
Rajeev rastogi <rajeev.rastogi@huawei.com>,
pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2014-01-10T21:34:58Z
Lists: pgsql-hackers
On 1/10/14, 12:59 PM, Joshua D. Drake wrote: > I know I am the one that instigated all of this so I want to be very clear on what I and what I am confident that my customers would expect. > > If a synchronous slave goes down, the master continues to operate. That is all. I don't care if it is configurable (I would be fine with that). I don't care if it is not automatic (e.g; slave goes down and we have to tell the master to continue). > > I have read through this thread more than once, and I have also went back to the docs. I understand why we do it the way we do it. I also understand that from a business requirement for 99% of CMD's customers, it's wrong. At least in the sense of providing continuity of service. +1 I understand that this is a degredation of full-on sync rep. But there is definite value added with sync-rep that can automatically (or at least easily) degrade over async; it protects you from single failures. I fully understand that it will not protect you from a double failure. That's OK in many cases. Jim C. Nasby, Data Architect jim@nasby.net 512.569.9461 (cell) http://jim.nasby.net