On Thu, Nov 9, 2017 at 4:17 PM, Andres Freund <and...@anarazel.de> wrote: >> Actually, on second thought, I take that back -- I don't think that >> REINDEXing will even finish once a HOT chain is broken by the bug. >> IndexBuildHeapScan() actually does quite a good job of making sure >> that HOT chains are sane, which is how the enhanced amcheck notices >> the bug here in practice. > > I think that's too optimistic.
Why? Because the "find the TID of the root" logic in IndexBuildHeapScan()/heap_get_root_tuples() won't reliably find the actual root (it might be some other HOT chain root following TID recycling by VACUUM)? Assuming that's what you meant: I would have thought that the xmin/xmax matching within heap_get_root_tuples() makes the sanity checking fairly reliable in practice. -- Peter Geoghegan -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers