Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-25 Thread Jaime Casanova
On Tue, Feb 23, 2010 at 11:08 AM, Alvaro Herrera wrote: > Steve Atkins wrote: > >> Would having a higher level process manager be adequate - one >> that spawns the postmaster and a list of associated processes >> (queue manager, job scheduler, random user daemons that are >> used for database appl

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-23 Thread Alvaro Herrera
Steve Atkins wrote: > Would having a higher level process manager be adequate - one > that spawns the postmaster and a list of associated processes > (queue manager, job scheduler, random user daemons that are > used for database application maintenance). It sounds like > something like that would

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-23 Thread Steve Atkins
On Feb 22, 2010, at 9:02 PM, Tom Lane wrote: > Alvaro Herrera writes: >> Regarding hooks or events, I think postmaster should be kept simple: >> launch at start, reset at crash recovery, kill at stop. Salt and pepper >> allowed but that's about it -- more complex ingredients are out of the >> q

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-23 Thread Alvaro Herrera
Simon Riggs wrote: > What is wanted is a means to integrate parts of a solution that are > already intimately tied to Postgres. Non-integration makes the whole > Postgres-based solution less reliable and harder to operate. Postgres > should not assume that it is the only aspect of the server: in a

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-23 Thread Simon Riggs
On Tue, 2010-02-23 at 00:02 -0500, Tom Lane wrote: > Alvaro Herrera writes: > > Regarding hooks or events, I think postmaster should be kept simple: > > launch at start, reset at crash recovery, kill at stop. Salt and pepper > > allowed but that's about it -- more complex ingredients are out of t

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-23 Thread Alvaro Herrera
Dimitri Fontaine wrote: > Tom Lane writes: > > Alvaro Herrera writes: > >> Regarding hooks or events, I think postmaster should be kept simple: > >> launch at start, reset at crash recovery, kill at stop. > > > > This is exactly why I think the whole proposal is a nonstarter. It is > > necessari

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-23 Thread Dimitri Fontaine
Tom Lane writes: > Alvaro Herrera writes: >> Regarding hooks or events, I think postmaster should be kept simple: >> launch at start, reset at crash recovery, kill at stop. > > This is exactly why I think the whole proposal is a nonstarter. It is > necessarily pushing more complexity into the po

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-22 Thread Tom Lane
Alvaro Herrera writes: > Regarding hooks or events, I think postmaster should be kept simple: > launch at start, reset at crash recovery, kill at stop. Salt and pepper > allowed but that's about it -- more complex ingredients are out of the > question due to added code to postmaster, which we wan

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-22 Thread Alvaro Herrera
David Christensen wrote: > What are the semantics? If you launch a process and it crashes, is > the postmaster responsible for relaunching it? Is there any > additional monitoring of that process it would be expected to do? > What defined hooks/events would you want to launch these processes > f

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-22 Thread David Christensen
On Feb 22, 2010, at 5:22 PM, Jaime Casanova wrote: On Mon, Feb 22, 2010 at 4:37 PM, Tom Lane wrote: Dimitri Fontaine writes: Tom Lane writes: This seems like a solution in search of a problem to me. The most salient aspect of such processes is that they would necessarily run as the postg

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-22 Thread Jaime Casanova
On Mon, Feb 22, 2010 at 4:37 PM, Tom Lane wrote: > Dimitri Fontaine writes: >> Tom Lane writes: >>> This seems like a solution in search of a problem to me.  The most >>> salient aspect of such processes is that they would necessarily run >>> as the postgres user > >> The precedent are archive a

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-22 Thread Dimitri Fontaine
Tom Lane writes: > Well, yeah, but you *must* trust those commands because every last bit > of your database content passes through their hands. That is not an > argument why you need to trust a scheduling facility --- much less the > tasks it schedules. It seems to me that CREATE FUNCTION maint

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-22 Thread Tom Lane
Dimitri Fontaine writes: > Tom Lane writes: >> This seems like a solution in search of a problem to me. The most >> salient aspect of such processes is that they would necessarily run >> as the postgres user > The precedent are archive and restore command. They do run as postgres > user too, do

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-22 Thread Merlin Moncure
On Mon, Feb 22, 2010 at 2:53 PM, Tom Lane wrote: > I still haven't seen a good reason for not using cron or Task Scheduler > or other standard tools. *) provided and popular feature in higher end databases *) the audience you cater to expects it *) IMO, it should simply not be necessary to inco

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-22 Thread Dimitri Fontaine
Tom Lane writes: > This seems like a solution in search of a problem to me. The most > salient aspect of such processes is that they would necessarily run > as the postgres user I happen to run my PGQ tickers and londiste daemons as "londiste" user and make it a superuser (at least while install

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-22 Thread Jaime Casanova
On Mon, Feb 22, 2010 at 3:08 PM, Jaime Casanova wrote: > On Mon, Feb 22, 2010 at 2:53 PM, Tom Lane wrote: >> >> I still haven't seen a good reason for not using cron or Task Scheduler >> or other standard tools. >> > > - marketing? don't you hate when people say: Oracle has it!? just before some

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-22 Thread Jaime Casanova
On Mon, Feb 22, 2010 at 2:53 PM, Tom Lane wrote: > > I still haven't seen a good reason for not using cron or Task Scheduler > or other standard tools. > - marketing? don't you hate when people say: Oracle has it!? - user dumbness: they forgot to start daemons they need (yes, i have seen that) or

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-22 Thread Tom Lane
Jaime Casanova writes: > wrote: >> API would be user_process_startup(), user_process_shutdown(). > so it should be a GUC, that is settable only at start time. > we need those integrated processes at all when in a standby server? This seems like a solution in search of a problem to me. The most

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-22 Thread Jaime Casanova
On Mon, Feb 22, 2010 at 1:50 PM, Heikki Linnakangas wrote: > >> we need those integrated processes at all when in a standby server? > > Yes. You might want to run e.g. scheduled reports from a standby > reporting server, launched by a scheduler process. Or backups. > ah! fair enough! -- Atentam

Re: [HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-22 Thread Heikki Linnakangas
Jaime Casanova wrote: > > if we can do this, how should it work? > Simon said: > """ > Yes, I think so. Rough design... > > integrated_user_processes = 'x, y, z' > > would run x(), y() and z() in their own processes. These would execute > after startup, or at consistent point in recovery. The cod

[HACKERS] tie user processes to postmaster was:(Re: [HACKERS] scheduler in core)

2010-02-22 Thread Jaime Casanova
On Mon, Feb 22, 2010 at 1:18 PM, Heikki Linnakangas wrote: > Jaime Casanova wrote: > >> so, is this idea (having some user processes be "tied" to postmaster >> start/stop) going to somewhere? > > I've added this to the TODO list. Now we just need someone to write it. > if we can do this, how shou