From owner-svn-src-all@FreeBSD.ORG Mon May 6 20:27:30 2013 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by hub.freebsd.org (Postfix) with ESMTP id 303DFE23; Mon, 6 May 2013 20:27:30 +0000 (UTC) (envelope-from pawel@dawidek.net) Received: from mail.dawidek.net (garage.dawidek.net [91.121.88.72]) by mx1.freebsd.org (Postfix) with ESMTP id EF45F1F1; Mon, 6 May 2013 20:27:29 +0000 (UTC) Received: from localhost (89-73-195-149.dynamic.chello.pl [89.73.195.149]) by mail.dawidek.net (Postfix) with ESMTPSA id 5DD4E5FB; Mon, 6 May 2013 22:23:28 +0200 (CEST) Date: Mon, 6 May 2013 22:29:52 +0200 From: Pawel Jakub Dawidek To: Konstantin Belousov Subject: Re: svn commit: r250027 - head/sys/kern Message-ID: <20130506202951.GB1390@garage.freebsd.pl> References: <201304281912.r3SJC9bL030636@svn.freebsd.org> <20130506181610.GA1390@garage.freebsd.pl> <20130506200530.GD3047@kib.kiev.ua> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="VrqPEDrXMn8OVzN4" Content-Disposition: inline In-Reply-To: <20130506200530.GD3047@kib.kiev.ua> X-OS: FreeBSD 10.0-CURRENT amd64 User-Agent: Mutt/1.5.21 (2010-09-15) Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 06 May 2013 20:27:30 -0000 --VrqPEDrXMn8OVzN4 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, May 06, 2013 at 11:05:30PM +0300, Konstantin Belousov wrote: > On Mon, May 06, 2013 at 08:16:11PM +0200, Pawel Jakub Dawidek wrote: > > On Sun, Apr 28, 2013 at 07:12:09PM +0000, Konstantin Belousov wrote: > > > Author: kib > > > Date: Sun Apr 28 19:12:09 2013 > > > New Revision: 250027 > > > URL: http://svnweb.freebsd.org/changeset/base/250027 > > >=20 > > > Log: > > > Eliminate the layering violation in the kern_sendfile(). When quer= ing > > > the file size, use VOP_GETATTR() instead of accessing vnode vm_obje= ct > > > un_pager.vnp.vnp_size. > >=20 > > Doesn't it add extra I/O to query file system about file's attributes? > > If it does, does it matter here? >=20 > It should not, typically. >=20 > E.g. UFS always keeps the unpacked inode in memory for any non-reclaimed > vnode. For NFS, vnode usually caches the attributes. I remember criticism on security.bsd.hardlink_check_[ug]id, because it added extra VOP_GETATTR() to the code path of link(2), which could hurt performance. sendfile(2) is different, as the file is open, so it should be fine indeed. --=20 Pawel Jakub Dawidek http://www.wheelsystems.com FreeBSD committer http://www.FreeBSD.org Am I Evil? Yes, I Am! http://mobter.com --VrqPEDrXMn8OVzN4 Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (FreeBSD) iEYEARECAAYFAlGIEr8ACgkQForvXbEpPzS9nwCeK3lE99kxonIFc6SSqdscihzt pewAn1BiuTD3qvSJIN6feHxXwEzvDsyb =tdEP -----END PGP SIGNATURE----- --VrqPEDrXMn8OVzN4--