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Date: Tue, 15 Jul 2008 15:39:09 -0700
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From: JINMEI Tatuya / =?ISO-2022-JP?B?GyRCP0BMQEMjOkgbKEI=?=
	<Jinmei_Tatuya@isc.org>
To: Bakul Shah <bakul@bitblocks.com>
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Cc: freebsd-net@freebsd.org, Kris Kennaway <kris@FreeBSD.org>,
	Thomas Vogt <freebsdlists@bsdunix.ch>
Subject: Re: too many open file descriptors messages since bind
	9.4.2-P1	(port dns94) 
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At Tue, 15 Jul 2008 15:12:31 -0700,
Bakul Shah <bakul@bitblocks.com> wrote:

> > Besides, I guess that the P1 versions severely suffer from heavy
> > overhead of select(2) when it regularly opens more than 1000 sockets.
> > Even if 'too many open file' messages are gone, many users won't
> > accept the increased load due to the overhead.  Beta versions use
> > kqueue, eliminating the fundamental overhead as well as the (too low)
> > limitation of # of descriptors.
> 
> Or more portably you can use poll(2).

I've not played with poll(2) in BIND9, but as far as I understand it,
it doesn't solve the fundamental overhead issue here.  For example,
the application should examine all possible descriptors even if only a
few of them are readable.

Anyway, since this is a FreeBSD specific list, I believe we can safely
assume the existence of kqueue, unless we are talking about a very old
version:-)

---
JINMEI, Tatuya
Internet Systems Consortium, Inc.