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Message-ID: <1200613953.478fea419c929@webmail.telus.net>
Date: Thu, 17 Jan 2008 15:52:33 -0800
From: Mischa Sandberg <mischa_sandberg@telus.net>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Stephen Frost <sfrost@snowman.net>, "Marc G. Fournier" <scrappy@hub.org>,
	pgsql-hackers@postgresql.org
Subject: Re: [ADMIN] postgresql in FreeBSD jails: proposal 
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Quoting Tom Lane <tgl@sss.pgh.pa.us>:

> Mischa Sandberg <mischa_sandberg@telus.net> writes:
> > I'm going to skip the kill(1,0) test and depend on nattch only,
> > with a function that PGSharedMemoryIsInUse() can also use.
> > (For a healthy server, nattch is never less than 2, right?)
> 
> Oh, forgot to mention: healthy servers are not the point here.
> You should make the code keep its hands off any segment with
> nonzero nattch, because even one orphaned backend is enough
> to cause trouble.

Note taken. Worth putting a warning in the log, too?

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Physicists think that reality approximates the equations.
Mathematicians never make the connection.