Skip site navigation (1) Skip section navigation (2)

Re: Re: [COMMITTERS] pgsql: Efficient transaction-controlled synchronous replication.

From: Markus Wanner <markus(at)bluegap(dot)ch>
To: Kevin Grittner <Kevin(dot)Grittner(at)wicourts(dot)gov>
Cc: Heikki Linnakangas <heikki(dot)linnakangas(at)enterprisedb(dot)com>, Simon Riggs <simon(at)2ndQuadrant(dot)com>, Alvaro Herrera <alvherre(at)commandprompt(dot)com>, Andrew Dunstan <andrew(at)dunslane(dot)net>, MARK CALLAGHAN <mdcallag(at)gmail(dot)com>, Aidan Van Dyk <aidan(at)highrise(dot)ca>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: Re: [COMMITTERS] pgsql: Efficient transaction-controlled synchronous replication.
Date: 2011-03-18 19:22:20
Message-ID: 4D83B0EC.1010105@bluegap.ch (view raw or flat)
Thread:
Lists: pgsql-committerspgsql-hackers
On 03/18/2011 05:27 PM, Kevin Grittner wrote:
> Basically, what Heikki addresses.  It has to be committed after
> crash and recovery, and deal with replicas which may or may not have
> been notified and may or may not have applied the transaction.

Huh?  I'm not quite following here.  Committing additional transactions
isn't a problem, reverting committed transactions is.

And yes, given that we only wait for ACK from a single standby, you'd
have to failover to exactly *that* standby to guarantee consistency.

> In fact, on further reflection, allowing other transactions to see
> work before the committing transaction returns could lead to broken
> behavior if that viewing transaction took some action based on the
> that, the master crashed, recovery was done using a standby, and
> that standby hadn't persisted the transaction.  So this behavior is
> necessary for good behavior.

I fully agree to that.

Regards

Markus

In response to

pgsql-hackers by date

Next:From: Simon RiggsDate: 2011-03-18 19:29:50
Subject: Re: Re: [COMMITTERS] pgsql: Efficient transaction-controlled synchronous replication.
Previous:From: Markus WannerDate: 2011-03-18 19:19:06
Subject: Re: Re: [COMMITTERS] pgsql: Efficient transaction-controlled synchronous replication.

pgsql-committers by date

Next:From: Simon RiggsDate: 2011-03-18 19:29:50
Subject: Re: Re: [COMMITTERS] pgsql: Efficient transaction-controlled synchronous replication.
Previous:From: Markus WannerDate: 2011-03-18 19:19:06
Subject: Re: Re: [COMMITTERS] pgsql: Efficient transaction-controlled synchronous replication.

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group