Glen Parker <glenebob@xxxxxxxxxx> writes: > I've re-read my original email and I just can't see how anybody got the > idea I was suggesting to not WAL record index changes. Mainly because the idea doesn't seem to make sense unless that's part of the package. If you don't cut index changes out of the WAL load then the savings on the base backup alone aren't going to be all that exciting when you consider the total cost of PITR backup. Furthermore, you would need some very ugly hacks on the recovery process to make it ignore (rather than try to apply) WAL records relating to indexes. I believe there are a fair number of cases where the recovery process doesn't even know that a particular file is an index, because the WAL stream doesn't tell it. The live backends generating the WAL log entries typically know that (and could suppress the entries) but the recovery process has only a very limited view of reality. It cannot, for example, trust the system catalogs to be in a correct/consistent state, so it couldn't look up the info for itself. BTW, there's a related problem with the idea, which is that the tools normally used to take base backups haven't got any way to distinguish indexes from any other kind of relation. regards, tom lane -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
