Re: elegant and effective way for running jobs inside a database

Alvaro Herrera <alvherre@commandprompt.com>

From: Alvaro Herrera <alvherre@commandprompt.com>

To: Merlin Moncure <mmoncure@gmail.com>

Cc: Dimitri Fontaine <dimitri@2ndquadrant.fr>, Josh Berkus <josh@agliodbs.com>, Pg Hackers <pgsql-hackers@postgresql.org>

Date: 2012-03-06T22:26:29Z

Lists: pgsql-hackers

Excerpts from Merlin Moncure's message of mar mar 06 19:07:51 -0300 2012:
> 
> On Tue, Mar 6, 2012 at 4:01 PM, Alvaro Herrera
> <alvherre@commandprompt.com> wrote:
> > Why do we need a ticker?  Just fetch the time of the task closest in the
> > future, and sleep till that time or a notify arrives (meaning schedule
> > change).
> 
> Because that can't be done in userland (at least, not without stored
> procedures) since you'd have to keep an open running transaction while
> sleeping.

I was thinking that the connection would be kept open but no query would
be running.  Does this preclude reception of notifies?  I mean, you
don't sleep via "SELECT pg_sleep()" but rather a select/poll in the
daemon.

-- 
Álvaro Herrera <alvherre@commandprompt.com>
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