Re: Yet another failure mode in pg_upgrade

On Sat, Sep  1, 2012 at 03:05:01PM -0400, Tom Lane wrote:
> Bruce Momjian <bruce@momjian.us> writes:
> > My point is that we are still going to need traditional connections for
> > live checks.
> 
> Yes, but that's not terribly relevant, IMO.  All it means is that we
> don't want to invent some solution that doesn't go through libpq.
> 
> > If we could find a solution for Windows, the socket in
> > current directory might be enough to lock things down, especially if we
> > put the socket in a new subdirectory that only we can read/write to. 
> 
> Who is "we"?  Somebody else logged in under the postgres userid could
> still connect.

But they have to find the current directory to do that;  seems unlikely.
They could kill -9 pg_upgrade too if they are the same user id.

> > Should I persue that in my patch?
> 
> I think this is just a band-aid, and we shouldn't be putting more
> effort into it than needed to ensure that unexpected configuration
> settings won't break it.  The right fix is a better form of
> standalone-backend mode.  Maybe I will go pursue that, since nobody
> else seems to want to.

I am worried that is going to be a complex solution to a very minor
problem.  Also, how is that going to get backpatched?

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + It's impossible for everything to be true. +