Re: WAL "low watermark" during base backup

From: Magnus Hagander <magnus(at)hagander(dot)net>
To: Dimitri Fontaine <dimitri(at)2ndquadrant(dot)fr>
Cc: Simon Riggs <simon(at)2ndquadrant(dot)com>, PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: WAL "low watermark" during base backup
Date: 2011-09-09 11:48:42
Message-ID: CABUevEz8NAXEE92ws7jA581ftSCqkDEXw2j+ZXdiT-KDAPyqpQ@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On Fri, Sep 9, 2011 at 13:40, Dimitri Fontaine <dimitri(at)2ndquadrant(dot)fr> wrote:
> Magnus Hagander <magnus(at)hagander(dot)net> writes:
>>> If you must have this then make pg_basebackup copy xlog files
>>> regularly during the backup. That way your backup can take forever and
>>> your primary disk won't fill up. In many cases it actually will take
>>> forever, but at least we don't take down the primary.
>>
>> There is a patch to do something like that as well sitting on the CF
>> page. I don't believe one necessarily excludes the other.
>
> I'm not getting why we need the later one when we have this older one?

One of them is for the simple case. It requires a single connection to
the server, and it supports things like writing to tarfiles and
compression.

The other one is more compelx. It uses multiple connections (one for
the base, one for the xlog), and as such doesn't support writing to
files, only directories.

--
 Magnus Hagander
 Me: http://www.hagander.net/
 Work: http://www.redpill-linpro.com/

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Peter Eisentraut 2011-09-09 12:02:14 Re: regress test failed
Previous Message Dimitri Fontaine 2011-09-09 11:40:29 Re: WAL "low watermark" during base backup