Re: HS/SR and smart shutdown

Josh Berkus <josh@agliodbs.com>

From: Josh Berkus <josh@agliodbs.com>
To: Simon Riggs <simon@2ndQuadrant.com>
Cc: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>, Fujii Masao <masao.fujii@gmail.com>, pgsql-hackers@postgresql.org
Date: 2010-01-30T00:01:15Z
Lists: pgsql-hackers
>> It's a good question if that still makes sense with Hot Standby.
>> Perhaps we should redefine smart shutdown in standby mode to shut down
>> as soon as all read-only connections have died.
> 
> It's clear that "smart" shutdown doesn't work while something is active.
> Recovery is "active" and so we shouldn't shutdown. It makes sense, it
> works like this already, lets leave it. Document it if needed.

I don't think it's clear, or intuitive for users.  In SR, recovery is
*never* done, so smart shutdown never completes (even if the master is
shut down, when I tested it).  This is particularly an important issue
when you consider that some/many service and init scripts only use smart
shutdown ... so we'll get a lot of "bug reports" of "posgresql does not
shut down".

HOWEVER, I do believe this is an issue we could live with for 9.0 if
it's going to lead to a whole lot of additional debugging of SR.  But if
it's an easy fix, it'll avoid a lot of complaints on pgsql-general.

--Josh Berkus