From:
Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To:
Alvaro Herrera <alvherre(at)commandprompt(dot)com>
Cc:
Simon Riggs <simon(at)2ndquadrant(dot)com>,
Heikki Linnakangas <heikki(at)enterprisedb(dot)com>,
pgsql-hackers(at)postgresql(dot)org, pgsql-patches(at)postgresql(dot)org
Subject:
Re: [HACKERS] WAL logging freezing
Date:
2006-10-31 16:23:40
Message-ID:
29850.1162311820@sss.pgh.pa.us (view raw or flat )
Thread:
2006-10-24 07:20:13 from Heikki Linnakangas <heikki(at)enterprisedb(dot)com>
2006-10-24 12:11:33 from Alvaro Herrera <alvherre(at)commandprompt(dot)com>
2006-10-24 14:11:43 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-10-27 15:44:52 from "Heikki Linnakangas" <heikki(at)enterprisedb(dot)com>
2006-10-27 16:01:12 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-10-27 21:19:54 from "Simon Riggs" <simon(at)2ndquadrant(dot)com>
2006-10-27 21:23:38 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-10-27 22:03:17 from "Simon Riggs" <simon(at)2ndquadrant(dot)com>
2006-10-30 13:42:27 from "Heikki Linnakangas" <heikki(at)enterprisedb(dot)com>
2006-10-30 14:08:37 from "Heikki Linnakangas" <heikki(at)enterprisedb(dot)com>
2006-10-30 16:20:56 from Alvaro Herrera <alvherre(at)commandprompt(dot)com>
2006-10-30 17:05:19 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-10-30 20:30:19 from "Simon Riggs" <simon(at)2ndquadrant(dot)com>
2006-10-30 21:39:58 from Alvaro Herrera <alvherre(at)commandprompt(dot)com>
2006-10-30 22:10:08 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-10-30 21:58:14 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-10-31 00:01:00 from "Simon Riggs" <simon(at)2ndquadrant(dot)com>
2006-10-31 00:18:50 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-10-31 00:58:40 from "Simon Riggs" <simon(at)2ndquadrant(dot)com>
2006-10-31 01:40:28 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-10-31 14:24:12 from "Simon Riggs" <simon(at)2ndquadrant(dot)com>
2006-10-31 10:41:10 from Heikki Linnakangas <heikki(at)enterprisedb(dot)com>
2006-10-31 15:06:40 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-10-31 16:04:55 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-10-31 19:49:27 from Gregory Stark <stark(at)enterprisedb(dot)com>
2006-10-31 19:56:59 from Alvaro Herrera <alvherre(at)commandprompt(dot)com>
2006-10-31 21:25:18 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-10-31 21:10:31 from "Simon Riggs" <simon(at)2ndquadrant(dot)com>
2006-11-01 14:50:56 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-11-02 21:50:31 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-11-02 23:57:08 from "Simon Riggs" <simon(at)2ndquadrant(dot)com>
2006-11-03 10:40:14 from "Zeugswetter Andreas ADI SD" <ZeugswetterA(at)spardat(dot)at>
2006-11-03 13:45:04 from Alvaro Herrera <alvherre(at)commandprompt(dot)com>
2006-11-04 17:35:16 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-11-05 09:21:05 from "Simon Riggs" <simon(at)2ndquadrant(dot)com>
2006-11-05 16:26:20 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-11-05 17:01:54 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-11-05 18:24:55 from "Simon Riggs" <simon(at)2ndquadrant(dot)com>
2006-11-05 18:28:34 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-11-05 19:47:28 from Gregory Stark <stark(at)enterprisedb(dot)com>
2006-11-05 21:39:25 from "Simon Riggs" <simon(at)2ndquadrant(dot)com>
2006-11-05 21:44:43 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-11-05 09:52:36 from "Heikki Linnakangas" <heikki(at)enterprisedb(dot)com>
2006-11-05 16:29:06 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
2006-10-31 16:23:40 from Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Lists:
pgsql-hackers pgsql-patches
Alvaro Herrera <alvherre(at)commandprompt(dot)com> writes:
> Simon Riggs wrote:
>> Ouch! We did discuss that also. Flushing the buffercache is nasty with
>> very large caches, so this makes autovacuum much less friendly - and
>> could take a seriously long time if you enforce the vacuum delay
>> costings.
> Hmm, isn't the buffer cache aware of a vacuum operation?
Yeah. What would probably happen is that we'd dump off most of the
dirtied pages to the kernel, which would likely still have a lot of them
in kernel buffers pending write. But then we'd have to fsync the table
--- so a physical write storm would ensue, which we have no way to
throttle.
I think the don't-truncate-clog approach is a much better answer.
regards, tom lane
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