On Fri, 2012-11-16 at 16:09 +0100, Andres Freund wrote: > As far as I understand the code the crash-safety aspects of the > visibilitymap currently rely on on having the knowledge that ALL_VISIBLE > has been cleared during a heap_(insert|update|delete). That allows > management of the visibilitymap without it being xlogged itself which > seems pretty important to me.
It looks like the xlrec does contain a "cleared all visible" flag in it, and it uses that to clear the VM as well as PD_ALL_VISIBLE. So, it still seems achievable, and maybe not even a large patch, to do away with PD_ALL_VISIBLE without a lot of performance risk. Regards, Jeff Davis -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers