Horton

Re: Standalone synchronous master

Joshua D. Drake <jd@commandprompt.com>

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From: "Joshua D. Drake" <jd@commandprompt.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Kevin Grittner <kgrittn@ymail.com>, Bruce Momjian <bruce@momjian.us>, Heikki Linnakangas <hlinnakangas@vmware.com>, Simon Riggs <simon@2ndQuadrant.com>, Rajeev rastogi <rajeev.rastogi@huawei.com>, "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2014-01-08T22:23:34Z
Lists: pgsql-hackers 
On 01/08/2014 01:55 PM, Tom Lane wrote:

> Sync mode is about providing a guarantee that the data exists on more than
> one server *before* we tell the client it's committed.  If you don't need
> that guarantee, you shouldn't be using sync mode.  If you do need it,
> it's not clear to me why you'd suddenly not need it the moment the going
> actually gets tough.

As I understand it what is being suggested is that if a subscriber or 
target goes down, then the master will just sit there and wait. When I 
read that, I read that the master will no longer process write 
transactions. If I am wrong in that understanding then cool. If I am not 
then that is a serious problem with a production scenario. There is an 
expectation that a master will continue to function if the target is 
down, synchronous or not.

Sincerely,

JD

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