Re: pg_start_backup and pg_stop_backup Re: Re: [COMMITTERS] pgsql: Make CheckRequiredParameterValues() depend upon correct

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>
Cc: Robert Haas <robertmhaas@gmail.com>, Simon Riggs <simon@2ndquadrant.com>, Fujii Masao <masao.fujii@gmail.com>, Alvaro Herrera <alvherre@commandprompt.com>, pgsql-hackers@postgresql.org
Date: 2010-04-28T17:53:47Z
Lists: pgsql-hackers
Heikki Linnakangas <heikki.linnakangas@enterprisedb.com> writes:
> Well, it would be nice to allow using pg_start_backup() on the primary
> when streaming replication is enabled, even if archiving isn't.
> Otherwise the only way to get the base backup for the standby is to shut
> down primary first, or use filesystem snapshot etc.

I think I must be missing something: exactly how would you fire up a new
standby from such a base backup, if you weren't running archiving?
If you aren't archiving then there's no guarantee that you'll still have
a continuous WAL series starting from the start of the backup.

IOW I think that the requirement in pg_start_backup shouldn't be relaxed
without some more thought/work.

			regards, tom lane