On Tue, Jun 2, 2015 at 11:36 AM, Andres Freund <andres@xxxxxxxxxxx> wrote: >> That would be a departure from the behavior of every existing release >> that includes this code based on, to my knowledge, zero trouble >> reports. > > On the other hand we're now at about bug #5 attributeable to the odd way > truncation works for multixacts. It's obviously complex and hard to get > right. It makes it harder to cope with the wrong values left in > datminxid etc. So I'm still wondering whether fixing this for good isn't > the better approach. It may well be. But I think we should do something more surgical first. Perhaps we can justify the pain and risk of making changes to the WAL format in the back-branches, but let's not do it in a rush. If we can get this patch to a state where it undoes the damage inflicted in 9.3.7/9.4.2, then we will be in a state where we have as much reliability as we had in 9.3.6 plus the protections against member-space wraparound added in 9.3.7 - which, like the patch I'm proposing now, were directly motivated by multiple, independent bug reports. That seems like a good place to get to. If nothing else, it will buy us some time to figure out what else we want to do. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
