From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ulrich Drepper Subject: Re: NFSv4/pNFS possible POSIX I/O API standards Date: Sun, 17 Dec 2006 13:51:38 -0800 Message-ID: <4585BBEA.6050705@redhat.com> References: <20061205220538.GA1988@infradead.org> <45760702.6040805@redhat.com> <20061206100614.GX5937@schatzie.adilger.int> <4576FBB0.2070704@redhat.com> <4576FD78.4040603@mcs.anl.gov> <4577011F.6040107@redhat.com> <20061206180124.GM17226@vestdata.no> <45770850.4030003@redhat.com> <20061217144130.GN25199@vestdata.no> <4585956F.80404@redhat.com> <20061217193821.GA21070@parisc-linux.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Ragnar Kj??rstad , Rob Ross , Christoph Hellwig , Trond Myklebust , Sage Weil , Brad Boyer , Anton Altaparmakov , Gary Grider , linux-fsdevel@vger.kernel.org Return-path: Received: from mx1.redhat.com ([66.187.233.31]:56992 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753060AbWLQVwN (ORCPT ); Sun, 17 Dec 2006 16:52:13 -0500 To: Matthew Wilcox In-Reply-To: <20061217193821.GA21070@parisc-linux.org> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org Matthew Wilcox wrote: > I know that the rsync load is a major factor on kernel.org right now. That should be quite easy to quantify then. Move the readdir and stat=20 call next to each other in the sources, pass the struct stat around if=20 necessary, and then count the stat calls which do not originate from th= e=20 stat following the readdir call. Of course we'll also need the actual=20 improvement which can be achieved by combining the calls. Given the=20 inodes are cached, is there more overhead then finding the right inode?= =20 Note that is rsync doesn't already use fstatat() it should do so and=20 this means then that there is no long file path to follow, all file=20 names are local to the directory opened with opendir(). My but feeling is that the improvements are minimal for normal (not=20 cluster etc) filesystems and hence the improvements for kernel.org woul= d=20 be minimal. --=20 =E2=9E=A7 Ulrich Drepper =E2=9E=A7 Red Hat, Inc. =E2=9E=A7 444 Castro S= t =E2=9E=A7 Mountain View, CA =E2=9D=96 - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel= " in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html