On Fri, 2007-03-30 at 11:27 +0100, Richard Huxton wrote: > Is that always true? Could the backup not pick up a partially-written > page? Assuming it's being written to as the backup is in progress. (We > are talking about when disk blocks are smaller than PG blocks here, so > can't guarantee an atomic write for a PG block?)
Any page written during a backup has a backup block that would not be removable by Koichi's tool, so yes, you'd still be safe. i.e. between pg_start_backup() and pg_stop_backup() we always use full page writes, even if you are running in full_page_writes=off mode. -- Simon Riggs EnterpriseDB http://www.enterprisedb.com ---------------------------(end of broadcast)--------------------------- TIP 7: You can help support the PostgreSQL project by donating at http://www.postgresql.org/about/donate
