Excerpts from Tom Lane's message of jue oct 20 19:20:19 -0300 2011: > So I've concluded that there's just no point in the GetOldestXmin > clamping, and we should just apply the xmin value we get from the > standby if it passes basic sanity checks (the epoch test), and hope that > we're not too late to prevent loss of the data the standby wanted.
I am happy that the HS patch has introduced uses for the xid epoch. I had to use them for multixact truncation in the FK locks patch, and was nervous because I wasn't seeing any user in core code other than the txid functions; this lack of callers, added to the comments in GetNextXidAndEpoch ("we do not support such things"), made me feel a bit uncomfortable about using it. I'm happy to have this problem out of my mind now. -- Álvaro Herrera <alvhe...@commandprompt.com> The PostgreSQL Company - Command Prompt, Inc. PostgreSQL Replication, Consulting, Custom Development, 24x7 support -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers