On Thu, 2007-01-25 at 22:19 -0500, Jan Wieck wrote: > The idea is to clone an existing serializable transactions snapshot > visibility information from one backend to another. The semantics would > be like this: > > backend1: start transaction; > backend1: set transaction isolation level serializable; > backend1: select pg_backend_pid(); > backend1: select publish_snapshot(); -- will block
Great idea. It can also be used by pg_dump to publish its snapshot so that we can make VACUUM continue to process effectively while it pg_dump is running. Two questions: - why does it have to block? I don't see any reason - the first process can begin doing useful work. The second process might fail or itself be blocked by something. - why just serializable snapshots? -- Simon Riggs EnterpriseDB http://www.enterprisedb.com ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
