Re: Updated backup APIs for non-exclusive backups

* Andres Freund (andres(at)anarazel(dot)de) wrote:
> On 2016-02-10 13:46:05 +0100, Magnus Hagander wrote:
> > * If the client disconnects with a non-exclusive backup running, the backup
> > is automatically aborted. This is the same thing that pg_basebackup does.
> > To use these non-exclusive backups the backup software will have to
> > maintain a persistent connection to the database -- something that should
> > not be a problem for any of the modern ones out there (but would've been
> > slightly trickier back in the days when we suggested shellscripts)
>
> I think we might want to make this one optional, but I'm not going to
> fight super hard for it.

I was thinking along the same lines.

> > * A new version of pg_stop_backup is created, taking an argument specifying
> > if it's exclusive or not. The current version of pg_stop_backup() continues
> > to work for exclusive backups, with no changes to behavior. The new
> > pg_stop_backup will return a record of three columns instead of just the
> > value -- the LSN (pglsn), the backup label file (text) and the tablespace
> > map file (text).
>
> I wonder if we shouldn't change the API a bit more aggressively. Right
> now we return the label and the map - but what if there's more files at
> some later point? One way would be to make it a SETOF function returning
> 'filename', 'content' or such. Makes it less clear what to do with the
> lsn admittedly.

If we make the 'client disconnect means abort' optional then we'd also
need to modify the API of stop backup to specify which backup to stop,
I'd think.

Thanks!

Stephen