Date: Wed, 28 Jul 2010 22:19:22 +0200
From: Andres Freund <andres@anarazel.de>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Robert Haas <robertmhaas@gmail.com>, Josh Berkus <josh@agliodbs.com>,
	Craig Ringer <craig@postnewspapers.com.au>,
	Matthew Wakeling <matthew@flymine.org>, pgsql-performance@postgresql.org
Subject: Re: Pooling in Core WAS: Need help in performance tuning.
Message-ID: <20100728201922.GA2984@anarazel.de>
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On Wed, Jul 28, 2010 at 04:10:08PM -0400, Tom Lane wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
> > However, if we don't support that, we can't do any sort of pooling-ish
> > thing without the ability to pass file descriptors between processes;
> > and Tom seems fairly convinced there's no portable way to do that.
>
> Well, what it would come down to is: are we prepared to not support
> pooling on platforms without such a capability?  It's certainly possible
> to do it on many modern platforms, but I don't believe we can make it
> happen everywhere.  Generally we've tried to avoid having major features
> that don't work everywhere ...
Which platforms do you have in mind here? All of the platforms I found
documented to be supported seem to support at least one of SCM_RIGHTS,
WSADuplicateSocket or STREAMS/FD_INSERT.
Most if not all beside windows support SCM_RIGHTS. The ones I am
dubious about support FD_INSERT...

Andres