Re: Online base backup from the hot-standby

Fujii Masao <masao.fujii@gmail.com>

From: Fujii Masao <masao.fujii@gmail.com>
To: Steve Singer <ssinger_pg@sympatico.ca>
Cc: Jun Ishiduka <ishizuka.jun@po.ntts.co.jp>, pgsql-hackers@postgresql.org, cedric.villemain.debian@gmail.com, robertmhaas@gmail.com, magnus@hagander.net, heikki.linnakangas@enterprisedb.com
Date: 2011-09-27T05:51:38Z
Lists: pgsql-hackers

Attachments

On Tue, Sep 27, 2011 at 11:56 AM, Fujii Masao <masao.fujii@gmail.com> wrote:
>> In backup.sgml  the new section titled "Making a Base Backup during
>> Recovery"  I would prefer to see some mention in the title that this
>> procedure is for standby servers ie "Making a Base Backup from a Standby
>> Database".  Users who have setup a hot-standby database should be familiar
>> with the 'standby' terminology. I agree that the "during recovery"
>> description is technically correct but I'm not sure someone who is looking
>> through the manual for instructions on making a base backup from here
>> standby will realize this is the section they should read.
>
> I used the term "recovery" rather than "standby" because we can take
> a backup even from the server in normal archive recovery mode but not
> standby mode. But there is not many users who take a backup during
> normal archive recovery, so I agree that the term "standby" is better to
> be used in the document. Will change.

Done.

>> Around line 969 where you give an example of copying the control file I
>> would be a bit clearer that this is an example command.  Ie (Copy the
>> pg_control file from the cluster directory to the global sub-directory of
>> the backup.  For example "cp $PGDATA/global/pg_control
>> /mnt/server/backupdir/global")
>
> Looks better. Will change.

Done.

>> or give an error message on
>> pg_stop_backup() saying that the base backup won't be usable.  The above
>> error doesn't really tell the user why there is a mismatch.
>
> What about the following error message?
>
> ERROR:  pg_stop_backup() was executed during normal processing though
> pg_start_backup() was executed during recovery
> HINT:  The database backup will not be usable.

Done. I attached the new version of the patch.

Regards,

-- 
Fujii Masao
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