Re: PITR Functional Design v2 for 7.5

Andreas Pflug <pgadmin@pse-consulting.de> writes:
> To clarify:
> I'd expect a cluster to be workable, if I
> - disable VACUUM until backup completed
> - issue CHECKPOINT
> - backup clog (CHECKPOINT and backup clog are the "backup checkpoint")
> - backup all datafiles (which include at least all completed transaction 
> data at checkpoint time)
> and then
> - restore datafiles and clog
> - bring up pgsql.

Why is that a useful approach?  You might as well shut down the
postmaster and do a cold filesystem backup, because you are depending on
the data files (including clog) not to change after the checkpoint.  You
cannot make such an assumption in a running database.

Preventing VACUUM does not help btw.
        regards, tom lane