From owner-freebsd-hackers@FreeBSD.ORG Mon Jan 13 20:19:24 2014 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 77E566CF for ; Mon, 13 Jan 2014 20:19:24 +0000 (UTC) Received: from bigwig.baldwin.cx (bigwig.baldwin.cx [IPv6:2001:470:1f11:75::1]) (using TLSv1 with cipher ADH-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 520161360 for ; Mon, 13 Jan 2014 20:19:24 +0000 (UTC) Received: from jhbbsd.localnet (unknown [209.249.190.124]) by bigwig.baldwin.cx (Postfix) with ESMTPSA id 07477B9AB; Mon, 13 Jan 2014 15:19:23 -0500 (EST) From: John Baldwin To: freebsd-hackers@freebsd.org Subject: Re: [patch] libc/resolv: use poll() instead of kqueue() Date: Mon, 13 Jan 2014 14:19:45 -0500 User-Agent: KMail/1.13.5 (FreeBSD/8.4-CBSD-20130906; KDE/4.5.5; amd64; ; ) References: <20140108225951.GB87058@stack.nl> In-Reply-To: <20140108225951.GB87058@stack.nl> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201401131419.45188.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.7 (bigwig.baldwin.cx); Mon, 13 Jan 2014 15:19:23 -0500 (EST) Cc: Jilles Tjoelker X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 13 Jan 2014 20:19:24 -0000 On Wednesday, January 08, 2014 5:59:52 pm Jilles Tjoelker wrote: > The resolver in libc creates a kqueue for watching a single file > descriptor. This can be done using poll() which should be lighter on the > kernel and reduce possible problems with rlimits (file descriptors, > kqueues). I agree that a kqueue for a single fd is a bit silly in terms of overhead compared to just calling poll. -- John Baldwin