This is what Postgres-XC is doing between a coordinator and a datanode. Coordinator may correspond to poolers/loadbalancers. Does anyone think it makes sense to extract XC implementation of snapshot shipping to PostgreSQL itself?
Cheers; ---------- Koichi Suzuki 2010/12/7 Stefan Kaltenbrunner <ste...@kaltenbrunner.cc>: > On 12/07/2010 01:22 AM, Tom Lane wrote: >> Josh Berkus <j...@agliodbs.com> writes: >>>> However, if you were doing something like parallel pg_dump you could >>>> just run the parent and child instances all against the slave, so the >>>> pg_dump scenario doesn't seem to offer much of a supporting use-case for >>>> worrying about this. When would you really need to be able to do it? >> >>> If you had several standbys, you could distribute the work of the >>> pg_dump among them. This would be a huge speedup for a large database, >>> potentially, thanks to parallelization of I/O and network. Imagine >>> doing a pg_dump of a 300GB database in 10min. >> >> That does sound kind of attractive. But to do that I think we'd have to >> go with the pass-the-snapshot-through-the-client approach. Shipping >> internal snapshot files through the WAL stream doesn't seem attractive >> to me. > > this kind of functionality would also be very useful/interesting for > connection poolers/loadbalancers that are trying to distribute load > across multiple hosts and could use that to at least give some sort of > consistency guarantee. > > > > Stefan > > -- > Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-hackers > -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
