Jim Nasby wrote: > That would be the minimal-impact version, yes. But I suspect if we went > through the trouble to do that, it would be just as easy to attempt the > freeze regardless of what scan_all is set to.
You mean if !scan_all we conditional-get the cleanup lock, if we get it then prune, if not then freeze? That seems nice on paper but I think it's useless because unless scan_all is true, then relfrozenxid doesn't advance anyway. > What I wish I knew is whether this problem was worth worrying about or not. > Hopefully the extra logging in 9.5 will shed some light at some point... As I recall, Andres says it isn't, but I have recollections of scans that take a very long time to finish because they keep running into a vacuum that has a page locked. -- Álvaro Herrera http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, 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
