Jeff Janes <jeff.ja...@gmail.com> writes: > I had a perhaps crazier idea. Aren't CLOG pages older than global xmin > effectively read only? Could backends that need these bypass locking > and shared memory altogether?
Hmm ... once they've been written out from the SLRU arena, yes. In fact you don't need to go back as far as global xmin --- *any* valid xmin is a sufficient boundary point. The only real problem is to know whether the data's been written out from the shared area yet. This idea has potential. I like it better than Robert's, mainly because I do not want to see us put something in place that would lead people to try to avoid rollbacks. regards, tom lane -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers