Re: Use of backup_label not noted in log

On Fri, Jan 19, 2024 at 09:32:26AM -0400, David Steele wrote:
> Any status on this patch? If we do back patch it would be nice to see this
> in the upcoming minor releases. I'm in favor of a back patch, as I think
> this is minimally invasive and would be very useful for debugging recovery
> issues.

I am not sure about the backpatch part, but on a second look I'm OK
with applying it on HEAD for now with the LOG added for the startup of
recovery when the backup_label file is read, for the recovery
completed from a backup, and for the restart from a backup.

> I like the phrasing you demonstrated in [1] but doesn't seem like there's a
> new patch for that, so I have attached one.

+       if (ControlFile->backupStartPoint != InvalidXLogRecPtr)

Nit 1: I would use XLogRecPtrIsInvalid here.

+       ereport(LOG,
+               (errmsg("completed backup recovery with redo LSN %X/%X",
+                       LSN_FORMAT_ARGS(oldBackupStartPoint))));

Nit 2: How about adding backupEndPoint in this LOG?  That would give:
"completed backup recovery with redo LSN %X/%X and end LSN %X/%X".
--
Michael