On Tue, May 10, 2011 at 6:02 PM, Robert Haas <robertmh...@gmail.com> wrote: > On Tue, May 10, 2011 at 12:57 PM, Simon Riggs <si...@2ndquadrant.com> wrote: >> Hmmm, do we really need to WAL log freezing? >> >> Can we break down freezing into a 2 stage process, so that we can have >> first stage as a lossy operation and a second stage that is WAL >> logged? > > That might solve the relfrozenxid problem - set the bits in the heap, > sync the heap, then update relfrozenxid once the heap is guaranteed > safely on disk - but it again seems problematic for Hot Standby.
How about we truncate the clog differently on each server? We could have a special kind of VACUUM that runs during Hot Standby, setting frozen hint bits only. -- Simon Riggs http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers