Re: [HACKERS] Re: [PATCHES] PostgreSQL virtual hosting support

[Bruce Momjian]

> Peter Eisentraut <[EMAIL PROTECTED]> writes:
> > What happened to the concerns that were raised?  The socket file is a lock
> > file, you cannot just move it around.
> 
> Good point.  IIRC, we rely on the socket file lock to ensure that you
> can't start two postmasters with the same port number.  (If both are
> started with -i, then you'll get a conflict on the IP port address,
> but if one or both is started without, then the socket-file lock is
> the only line of defense.)  This is important because shared memory
> keys are derived from the port number.  I'm not sure that the code
> will behave in a pleasant manner when two postmasters try to use the
> same shared memory block --- most likely, death and destruction will
> ensue.
> 
> I think we had some discussions about changing the way that shared
> memory keys are generated, which might make this a less critical issue.
> But until something's done about that, this patch looks awfully
> dangerous.

But do we yank it out for that reason?  I don't think so.

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