Re: PITR, checkpoint, and local relations

Vadim Mikheev <vmikheev@sectorbase.com>

From: "Mikheev, Vadim" <vmikheev@SECTORBASE.COM>
To: "'Tom Lane'" <tgl@sss.pgh.pa.us>, richt@multera.com
Cc: "J. R. Nield" <jrnield@usol.com>, Bruce Momjian <pgman@candle.pha.pa.us>, PostgreSQL Hacker <pgsql-hackers@postgresql.org>
Date: 2002-08-03T00:00:25Z
Lists: pgsql-hackers
> I really dislike the notion of turning off checkpointing.  What if the
> backup process dies or gets stuck (eg, it's waiting for some 
> operator to
> change a tape, but the operator has gone to lunch)?  IMHO, backup
> systems that depend on breaking the system's normal 
> operational behavior
> are broken.  It should be sufficient to force a checkpoint when you
> start and when you're done --- altering normal operation in between is
> a bad design.

But you have to prevent log files reusing while you copy data files.
That's why I asked are 3 commands from pg_copy required and couldn't
be backup accomplished by issuing single command

ALTER SYSTEM BACKUP <dir | stdout (to copy data to client side)>

(even from pgsql) so backup process would die with entire system -:)
As for tape changing, maybe we could use some timeout and then just
stop backup process.

Vadim