On 12/22/17 00:29, Michael Paquier wrote: > exclusive backup API can lead to problems? Imagine the case where > you take a exclusive backup and the instance from which a backup is > taken crashes, *with* a backup_label file on disk. Oops. That's one > reason behind non-exclusive backups, which is what pg_basebackup
I was noticing that terminology in the long backup-from-standby thread I was reading, but it wasn't clear to me how the terms originated. What's exclusive about pg_start_backup/copy/pg_stop_backup? And what's nonexclusive about pg_basebackup (which, AFAICS, is following roughly the same sequence under the hood)? By the way, what does happen in that case? I'm guessing it wakes up, sees the backup_label file, decides it's doing a PITR, and starts replaying already-applied WAL from the start-of-backup checkpoint, rather than from the most recent one? Oops. -Chap
