From:
Hannu Krosing <hannu(at)krosing(dot)net>
To:
Robert Treat <xzilla(at)users(dot)sourceforge(dot)net>
Cc:
Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Greg Smith <gsmith(at)gregsmith(dot)com>,"Joshua D(dot) Drake" <jd(at)commandprompt(dot)com>,Andrew Dunstan <andrew(at)dunslane(dot)net>, pgsql-hackers(at)postgresql(dot)org,Bruce Momjian <bruce(at)momjian(dot)us>, David Fetter <david(at)fetter(dot)org>,Josh Berkus <josh(at)agliodbs(dot)com>, Marko Kreen <markokr(at)gmail(dot)com>
Subject:
Re: Core team statement on replication in PostgreSQL
Date:
2008-06-01 20:42:11
Message-ID:
1212352931.18365.17.camel@huvostro (view raw or flat )
Thread:
2008-05-29 14:12:55 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-05-29 14:54:03 from "Marko Kreen" <markokr(at)gmail(dot)com>
2008-05-29 15:58:19 from Rick Vernam <rickv(at)hobi(dot)com>
2008-05-29 18:49:14 from Teodor Sigaev <teodor(at)sigaev(dot)ru>
2008-05-29 19:22:09 from "Marko Kreen" <markokr(at)gmail(dot)com>
2008-05-29 15:21:05 from David Fetter <david(at)fetter(dot)org>
2008-05-29 15:40:57 from "Marko Kreen" <markokr(at)gmail(dot)com>
2008-05-29 15:49:54 from Josh Berkus <josh(at)agliodbs(dot)com>
2008-05-29 15:58:31 from Bruce Momjian <bruce(at)momjian(dot)us>
2008-05-29 16:12:02 from David Fetter <david(at)fetter(dot)org>
2008-05-29 16:13:20 from Bruce Momjian <bruce(at)momjian(dot)us>
2008-05-29 21:42:16 from Robert Treat <xzilla(at)users(dot)sourceforge(dot)net>
2008-05-29 21:52:37 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-05-29 21:54:36 from "Joshua D(dot) Drake" <jd(at)commandprompt(dot)com>
2008-05-29 22:39:53 from Andrew Dunstan <andrew(at)dunslane(dot)net>
2008-05-29 22:47:05 from "Joshua D(dot) Drake" <jd(at)commandprompt(dot)com>
2008-05-29 23:02:56 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-05-29 23:12:22 from "Joshua D(dot) Drake" <jd(at)commandprompt(dot)com>
2008-05-30 00:14:30 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-05-30 00:57:21 from Aidan Van Dyk <aidan(at)highrise(dot)ca>
2008-05-30 01:25:49 from "Joshua D(dot) Drake" <jd(at)commandprompt(dot)com>
2008-05-30 00:25:10 from "Merlin Moncure" <mmoncure(at)gmail(dot)com>
2008-05-30 00:31:31 from Greg Smith <gsmith(at)gregsmith(dot)com>
2008-05-30 01:26:36 from Josh Berkus <josh(at)agliodbs(dot)com>
2008-05-30 02:59:21 from "Merlin Moncure" <mmoncure(at)gmail(dot)com>
2008-05-30 19:16:57 from Robert Treat <xzilla(at)users(dot)sourceforge(dot)net>
2008-05-30 03:02:56 from Andrew Dunstan <andrew(at)dunslane(dot)net>
2008-05-30 14:19:00 from Andreas 'ads' Scherbaum <adsmail(at)wars-nicht(dot)de>
2008-05-30 20:22:41 from Greg Smith <gsmith(at)gregsmith(dot)com>
2008-05-30 21:18:51 from "Gurjeet Singh" <singh(dot)gurjeet(at)gmail(dot)com>
2008-05-30 22:11:20 from Greg Smith <gsmith(at)gregsmith(dot)com>
2008-05-31 03:39:14 from "Gurjeet Singh" <singh(dot)gurjeet(at)gmail(dot)com>
2008-05-31 00:00:17 from "Joshua D(dot) Drake" <jd(at)commandprompt(dot)com>
2008-05-30 22:42:20 from Andreas 'ads' Scherbaum <adsmail(at)wars-nicht(dot)de>
2008-06-10 01:46:06 from Bruce Momjian <bruce(at)momjian(dot)us>
2008-06-10 01:49:52 from Alvaro Herrera <alvherre(at)commandprompt(dot)com>
2008-06-10 01:55:31 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-06-10 02:48:33 from Greg Smith <gsmith(at)gregsmith(dot)com>
2008-06-10 03:16:11 from "Koichi Suzuki" <koichi(dot)szk(at)gmail(dot)com>
2008-06-10 09:43:51 from Gregory Stark <stark(at)enterprisedb(dot)com>
2008-06-10 10:03:08 from "Heikki Linnakangas" <heikki(at)enterprisedb(dot)com>
2008-06-16 16:56:51 from "Kevin Grittner" <Kevin(dot)Grittner(at)wicourts(dot)gov>
2008-07-10 00:55:25 from Robert Hodges <robert(dot)hodges(at)continuent(dot)com>
2008-07-10 11:56:31 from "Marko Kreen" <markokr(at)gmail(dot)com>
2008-07-10 14:44:20 from Robert Hodges <robert(dot)hodges(at)continuent(dot)com>
2008-07-11 21:03:14 from chris <cbbrowne(at)ca(dot)afilias(dot)info>
2008-07-15 15:03:55 from Bruce Momjian <bruce(at)momjian(dot)us>
2008-07-15 22:18:46 from Alvaro Herrera <alvherre(at)commandprompt(dot)com>
2008-07-15 22:24:17 from Bruce Momjian <bruce(at)momjian(dot)us>
2008-07-15 22:32:08 from Alvaro Herrera <alvherre(at)commandprompt(dot)com>
2008-07-15 22:56:31 from Bruce Momjian <bruce(at)momjian(dot)us>
2008-05-30 21:05:57 from Andrew Dunstan <andrew(at)dunslane(dot)net>
2008-05-30 22:47:19 from Andreas 'ads' Scherbaum <adsmail(at)wars-nicht(dot)de>
2008-05-31 06:18:08 from "Mike Rylander" <mrylander(at)gmail(dot)com>
2008-05-31 14:21:41 from "Merlin Moncure" <mmoncure(at)gmail(dot)com>
2008-05-31 15:14:48 from "Joshua D(dot) Drake" <jd(at)commandprompt(dot)com>
2008-05-30 22:51:57 from Josh Berkus <josh(at)agliodbs(dot)com>
2008-05-31 00:56:19 from Tatsuo Ishii <ishii(at)postgresql(dot)org>
2008-05-31 01:32:26 from Andrew Dunstan <andrew(at)dunslane(dot)net>
2008-06-02 15:52:05 from Chris Browne <cbbrowne(at)acm(dot)org>
2008-06-02 20:40:47 from Andreas 'ads' Scherbaum <adsmail(at)wars-nicht(dot)de>
2008-06-03 07:19:59 from Hannu Krosing <hannu(at)krosing(dot)net>
2008-05-30 05:10:20 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-05-30 07:01:46 from "Gurjeet Singh" <singh(dot)gurjeet(at)gmail(dot)com>
2008-05-30 13:31:06 from "Marko Kreen" <markokr(at)gmail(dot)com>
2008-05-30 15:59:23 from "Merlin Moncure" <mmoncure(at)gmail(dot)com>
2008-05-30 14:43:00 from Simon Riggs <simon(at)2ndquadrant(dot)com>
2008-05-30 14:46:19 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-05-30 15:30:14 from Andrew Dunstan <andrew(at)dunslane(dot)net>
2008-05-30 15:58:03 from Simon Riggs <simon(at)2ndquadrant(dot)com>
2008-06-10 01:25:17 from Bruce Momjian <bruce(at)momjian(dot)us>
2008-06-10 01:50:58 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-06-10 16:01:05 from Josh Berkus <josh(at)agliodbs(dot)com>
2008-06-11 01:11:07 from ITAGAKI Takahiro <itagaki(dot)takahiro(at)oss(dot)ntt(dot)co(dot)jp>
2008-05-30 08:56:45 from Simon Riggs <simon(at)2ndquadrant(dot)com>
2008-05-30 19:16:29 from Robert Treat <xzilla(at)users(dot)sourceforge(dot)net>
2008-06-01 20:42:11 from Hannu Krosing <hannu(at)krosing(dot)net>
2008-06-04 04:08:46 from "Stephen Denne" <Stephen(dot)Denne(at)datamail(dot)co(dot)nz>
2008-06-04 08:13:52 from "Heikki Linnakangas" <heikki(at)enterprisedb(dot)com>
2008-06-04 10:51:26 from Teodor Sigaev <teodor(at)sigaev(dot)ru>
2008-06-04 11:19:42 from "Heikki Linnakangas" <heikki(at)enterprisedb(dot)com>
2008-06-04 10:58:53 from Csaba Nagy <nagy(at)ecircle-ag(dot)com>
2008-06-04 11:17:55 from "Heikki Linnakangas" <heikki(at)enterprisedb(dot)com>
2008-06-04 17:18:17 from Jeff Davis <pgsql(at)j-davis(dot)com>
2008-06-04 18:23:38 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-06-04 18:26:02 from Jeff Davis <pgsql(at)j-davis(dot)com>
2008-06-05 11:08:14 from Gregory Stark <stark(at)enterprisedb(dot)com>
2008-06-04 14:40:58 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-06-04 15:27:04 from Hannu Krosing <hannu(at)krosing(dot)net>
2008-06-04 15:37:25 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-06-04 16:16:40 from Simon Riggs <simon(at)2ndquadrant(dot)com>
2008-06-05 00:10:26 from "Koichi Suzuki" <koichi(dot)szk(at)gmail(dot)com>
2008-06-05 00:30:34 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-06-05 04:21:25 from "Koichi Suzuki" <koichi(dot)szk(at)gmail(dot)com>
2008-05-30 19:16:34 from Robert Treat <xzilla(at)users(dot)sourceforge(dot)net>
2008-05-30 02:38:28 from Andrew Sullivan <ajs(at)commandprompt(dot)com>
2008-05-29 22:12:31 from Dimitri Fontaine <dim(at)hi-media(dot)com>
2008-05-29 22:29:01 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-05-30 08:29:30 from Dimitri Fontaine <dfontaine(at)hi-media(dot)com>
2008-05-30 09:02:03 from Dimitri Fontaine <dfontaine(at)hi-media(dot)com>
2008-05-30 14:26:53 from Andreas 'ads' Scherbaum <adsmail(at)wars-nicht(dot)de>
2008-05-29 16:22:26 from Steve Atkins <steve(at)blighty(dot)com>
2008-05-30 14:42:10 from Andreas 'ads' Scherbaum <adsmail(at)wars-nicht(dot)de>
2008-05-29 19:54:03 from Peter Eisentraut <peter_e(at)gmx(dot)net>
2008-05-29 20:39:29 from David Fetter <david(at)fetter(dot)org>
2008-05-29 20:44:19 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-05-29 20:50:51 from David Fetter <david(at)fetter(dot)org>
2008-05-29 20:54:04 from Bruce Momjian <bruce(at)momjian(dot)us>
2008-05-29 20:58:34 from David Fetter <david(at)fetter(dot)org>
2008-05-30 13:29:03 from Andrew Sullivan <ajs(at)commandprompt(dot)com>
2008-05-29 21:00:29 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-05-29 20:55:42 from Josh Berkus <josh(at)agliodbs(dot)com>
2008-05-29 21:02:08 from David Fetter <david(at)fetter(dot)org>
2008-05-29 21:09:28 from Josh Berkus <josh(at)agliodbs(dot)com>
2008-05-29 21:29:01 from Andrew Sullivan <ajs(at)commandprompt(dot)com>
2008-05-29 16:18:44 from Josh Berkus <josh(at)agliodbs(dot)com>
2008-05-29 16:20:55 from Bruce Momjian <bruce(at)momjian(dot)us>
2008-05-29 17:41:32 from Jeff Davis <pgsql(at)j-davis(dot)com>
2008-05-29 19:56:12 from Peter Eisentraut <peter_e(at)gmx(dot)net>
2008-05-29 16:10:05 from Aidan Van Dyk <aidan(at)highrise(dot)ca>
2008-05-29 15:46:22 from "Joshua D(dot) Drake" <jd(at)commandprompt(dot)com>
2008-05-29 15:48:25 from "Douglas McNaught" <doug(at)mcnaught(dot)org>
2008-05-29 16:00:55 from "Dave Page" <dpage(at)pgadmin(dot)org>
2008-05-29 16:16:15 from Aidan Van Dyk <aidan(at)highrise(dot)ca>
2008-05-29 16:27:38 from "Marko Kreen" <markokr(at)gmail(dot)com>
2008-05-29 16:35:41 from Aidan Van Dyk <aidan(at)highrise(dot)ca>
2008-06-01 20:16:51 from James Mansion <james(at)mansionfamily(dot)plus(dot)com>
2008-05-29 16:19:48 from Andrew Dunstan <andrew(at)dunslane(dot)net>
2008-05-29 16:40:14 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-05-29 19:03:40 from "Merlin Moncure" <mmoncure(at)gmail(dot)com>
2008-05-29 19:59:55 from Peter Eisentraut <peter_e(at)gmx(dot)net>
2008-05-29 20:22:13 from "Merlin Moncure" <mmoncure(at)gmail(dot)com>
2008-05-29 15:53:03 from David Fetter <david(at)fetter(dot)org>
2008-05-29 17:37:14 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-05-29 19:05:18 from Robert Hodges <robert(dot)hodges(at)continuent(dot)com>
2008-05-29 19:16:57 from "Merlin Moncure" <mmoncure(at)gmail(dot)com>
2008-06-01 15:58:59 from Robert Hodges <robert(dot)hodges(at)continuent(dot)com>
2008-06-01 17:19:10 from "Merlin Moncure" <mmoncure(at)gmail(dot)com>
2008-06-01 17:43:22 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-06-04 03:20:11 from Andrew Sullivan <ajs(at)commandprompt(dot)com>
2008-06-04 07:24:20 from Markus Schiltknecht <markus(at)bluegap(dot)ch>
2008-06-04 14:36:23 from Andrew Sullivan <ajs(at)commandprompt(dot)com>
2008-05-29 19:30:07 from Andrew Sullivan <ajs(at)commandprompt(dot)com>
2008-05-29 20:09:47 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2008-05-29 22:06:39 from Chris Browne <cbbrowne(at)acm(dot)org>
2008-05-30 18:12:51 from Robert Hodges <robert(dot)hodges(at)continuent(dot)com>
2008-05-30 19:57:28 from Simon Riggs <simon(at)2ndquadrant(dot)com>
2008-05-29 20:35:41 from Josh Berkus <josh(at)agliodbs(dot)com>
2008-06-01 21:14:39 from Hannu Krosing <hannu(at)krosing(dot)net>
2008-06-02 06:37:30 from Robert Hodges <robert(dot)hodges(at)continuent(dot)com>
2008-05-29 19:33:41 from "Marko Kreen" <markokr(at)gmail(dot)com>
2008-06-01 20:42:29 from Hannu Krosing <hannu(at)krosing(dot)net>
2008-05-29 16:10:26 from Josh Berkus <josh(at)agliodbs(dot)com>
2008-05-29 16:29:58 from "Joshua D(dot) Drake" <jd(at)commandprompt(dot)com>
2008-05-29 18:05:12 from Josh Berkus <josh(at)agliodbs(dot)com>
2008-05-29 20:08:11 from Peter Eisentraut <peter_e(at)gmx(dot)net>
2008-05-29 16:20:37 from "Marko Kreen" <markokr(at)gmail(dot)com>
2008-05-29 18:20:04 from Andrew Sullivan <ajs(at)commandprompt(dot)com>
2008-05-29 20:10:13 from Peter Eisentraut <peter_e(at)gmx(dot)net>
2008-05-29 16:11:21 from Brian Hurt <bhurt(at)janestcapital(dot)com>
2008-05-29 18:13:26 from Andrew Sullivan <ajs(at)commandprompt(dot)com>
2008-05-29 18:28:08 from David Fetter <david(at)fetter(dot)org>
2008-05-29 19:21:24 from Brian Hurt <bhurt(at)janestcapital(dot)com>
2008-05-29 17:11:08 from Shane Ambler <pgsql(at)Sheeky(dot)Biz>
2008-05-29 17:39:48 from Greg Smith <gsmith(at)gregsmith(dot)com>
2008-06-01 19:57:00 from James Mansion <james(at)mansionfamily(dot)plus(dot)com>
2008-05-29 16:01:44 from Mathias Brossard <mathias(dot)brossard(at)opentrust(dot)com>
2008-05-29 20:12:54 from Peter Eisentraut <peter_e(at)gmx(dot)net>
2008-05-29 21:37:44 from Mathias Brossard <mathias(dot)brossard(at)opentrust(dot)com>
2008-06-02 17:37:59 from Hannu Krosing <hannu(at)krosing(dot)net>
2008-05-29 20:14:14 from Peter Eisentraut <peter_e(at)gmx(dot)net>
2008-05-30 08:29:17 from Simon Riggs <simon(at)2ndquadrant(dot)com>
2008-05-30 10:21:53 from Dirk Riehle <dirk(at)riehle(dot)org>
2008-05-31 18:48:26 from Josh Berkus <josh(at)agliodbs(dot)com>
2008-06-01 03:22:23 from Robert Treat <xzilla(at)users(dot)sourceforge(dot)net>
2008-06-01 13:31:44 from Dirk Riehle <dirk(at)riehle(dot)org>
2008-06-01 05:23:21 from Shane Ambler <pgsql(at)Sheeky(dot)Biz>
2008-06-01 14:56:10 from "Jonah H(dot) Harris" <jonah(dot)harris(at)gmail(dot)com>
2008-05-30 20:21:28 from "Gurjeet Singh" <singh(dot)gurjeet(at)gmail(dot)com>
2008-06-01 18:31:13 from "Dawid Kuroczko" <qnex42(at)gmail(dot)com>
Lists:
pgsql-advocacy pgsql-hackers
On Fri, 2008-05-30 at 15:16 -0400, Robert Treat wrote:
> On Friday 30 May 2008 01:10:20 Tom Lane wrote:
> > Greg Smith <gsmith(at)gregsmith(dot)com> writes:
> > > I fully accept that it may be the case that it doesn't make technical
> > > sense to tackle them in any order besides sync->read-only slaves because
> > > of dependencies in the implementation between the two.
> >
> > Well, it's certainly not been my intention to suggest that no one should
> > start work on read-only-slaves before we finish the other part. The
> > point is that I expect the log shipping issues will be done first
> > because they're easier, and it would be pointless to not release that
> > feature if we had it.
> >
> > But since you mention it: one of the plausible answers for fixing the
> > vacuum problem for read-only slaves is to have the slaves push an xmin
> > back upstream to the master to prevent premature vacuuming. The current
> > design of pg_standby is utterly incapable of handling that requirement.
> > So there might be an implementation dependency there, depending on how
> > we want to solve that problem.
> >
>
> Sure, but whose to say that after synchronous wal shipping is "finished" it
> wont need a serious re-write due to new needs from the hot standby feature. I
> think going either way carries some risk.
The simplest form of synchronous wal shipping would not even need
postgresql running on slave, just a small daemon which reports when wal
blocks are a) received and b) synced to disk.
This setup would just guarantee "no data loss on single machine
failure". form there on you could add various features, including
support for both switchover and failover, async replication to multiple
slaves, etc.
the only thing that needs anything additional from slave wal-receiving
daemon is when you want the kind of wal-sync which would guarantee that
read-only query on slave issued after commit returns from master sees
latest data. for this kinds of guarantees you need at least feedback
about wal-replay, but possibly also shared transaction numbers and
shared snapshots, to be sure that OLTP type queries see the latest and
OLAP queries are not denied seeing VACUUMED on master.
--------------
Hannu
In response to
Responses
pgsql-hackers by date
Next :From: Hannu KrosingDate: 2008-06-01 20:42:29Subject : Re: Core team statement on replication in PostgreSQLPrevious :From : James MansionDate : 2008-06-01 20:16:51Subject : Re: Core team statement on replication in PostgreSQL
pgsql-advocacy by date
Next :From: Hannu KrosingDate: 2008-06-01 20:42:29Subject : Re: Core team statement on replication in PostgreSQLPrevious :From : James MansionDate : 2008-06-01 20:16:51Subject : Re: Core team statement on replication in PostgreSQL
