2012/3/7 Simon Riggs <si...@2ndquadrant.com>: > On Tue, Mar 6, 2012 at 3:21 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: > >> But having said that, it's not apparent to me why such a thing would >> need to live "inside the database" at all. It's very easy to visualize >> a task scheduler that runs as a client and requires nothing new from the >> core code. Approaching the problem that way would let the scheduler >> be an independent project that stands or falls on its own merits. > > On Tue, Mar 6, 2012 at 4:36 PM, Alvaro Herrera > <alvhe...@commandprompt.com> wrote: > >> What such an external scheduler would need from core is support for >> starting up and shutting down along postmaster (as well as restarts at >> appropriate times). Postmaster already has the ability to start and >> shut down many processes depending on several different policies; I >> think it's mostly a matter of exporting that functionality in a sane way. > > Tom's question is exactly on the money, and so is Alvaro's answer. > > Many, many people have requested code that "runs in core", but the key > point is that all they actually want are the core features required to > build one. The actual projects actively want to live outside of core. > The "run in core" bit is actually just what Alvaro says, the ability > to interact gracefully for startup and shutdown. > > What I think we need is an API like the LWlock add in requests, so we > can have a library that requests it is assigned a daemon to run in, > looking very much like autovacuum launcher, with the guts removed. It > would then be a matter for the code authors as to whether it was a > client program that interacts with server, or whether it was a full > blown daemon like autovacuum. >
it is true - first step should be short - and maintaining, assign to jobs and others can be implemented as extension. There is not necessary SQL api (other than functions). Regards Pavel > We talked about this at last year's Dev meeting. And we got > sidetracked into "what we really want is stored procedures". Maybe we > want that, but its a completely separate thing. Please lets not get > distracted from a very simple thing because of the existence of other > requirements. > > -- > Simon Riggs http://www.2ndQuadrant.com/ > PostgreSQL Development, 24x7 Support, Training & Services > > -- > 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
