Robert Haas <robertmh...@gmail.com> writes: > I think the real trick is figuring out a design that can improve > concurrency.
I'm far from familiar with the detailed concepts here, but allow me to comment. I have two open questions: - is it possible to use a distributed algorithm to produce XIDs, something like Vector Clocks? Then each backend is able to create a snapshot (well, and XID) on its own, and any backend is still able to compare its snapshot to any other snapshot (well, XID) - is it possible to cache the production of the next snapshots so that generating an XID only means getting the next in a pre-computed vector? My guess by reading the emails here is that we need to add some information at snapshot generation time, it's not just about getting a 32 bit sequence number. I'm not sure I'm being that helpful here, but sometime stating the obviously impossible ideas allows to think about some new design, so I figured I would still try :) Regards, -- Dimitri Fontaine http://2ndQuadrant.fr PostgreSQL : Expertise, Formation et Support -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers