On Tue, Aug 14, 2012 at 11:54:53PM -0400, Peter Eisentraut wrote:
> On Tue, 2012-08-14 at 17:56 -0400, Tom Lane wrote:
> > Peter Eisentraut <peter_e@gmx.net> writes:
> > > On 8/10/12 7:48 PM, Dimitri Fontaine wrote:
> > >> What about having single user mode talk fe/be protocol, and talk to it via a UNIX pipe, with pg_upgrade starting
thesingle user backend as a subprocess?
> >
> > > I think that's essentially equivalent to starting the server on a
> > > Unix-domain socket in a private directory. But that has been rejected
> > > because it doesn't work on Windows.
> >
> > > The question in my mind is, is there some other usable way on Windows
> > > for two unrelated processes to communicate over file descriptors in a
> > > private and secure way?
> >
> > You're making this unnecessarily hard, because there is no need for the
> > two processes to be unrelated.
> >
> > The implementation I'm visualizing is that a would-be client (think psql
> > or pg_dump, though the code would actually be in libpq) forks off a
> > process that becomes a standalone backend, and then they communicate
> > over a pair of pipes that were created before forking. This is
> > implementable on any platform that supports Postgres, because initdb
> > already relies on equivalent capabilities.
>
> Well, that would be an interesting feature, but it's debatable which
> among this or just adding a new socket type (if available) is harder.
TODO added:
Find cleaner way to start/stop dedicated servers for upgrades
http://archives.postgresql.org/pgsql-hackers/2012-08/msg00275.php
-- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB
http://enterprisedb.com
+ It's impossible for everything to be true. +
