From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267385AbUG2AdH (ORCPT ); Wed, 28 Jul 2004 20:33:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267376AbUG2AaZ (ORCPT ); Wed, 28 Jul 2004 20:30:25 -0400 Received: from parcelfarce.linux.theplanet.co.uk ([195.92.249.252]:48530 "EHLO www.linux.org.uk") by vger.kernel.org with ESMTP id S267395AbUG2A32 (ORCPT ); Wed, 28 Jul 2004 20:29:28 -0400 Date: Thu, 29 Jul 2004 01:29:24 +0100 From: viro@parcelfarce.linux.theplanet.co.uk To: "David S. Miller" Cc: Chris Wedgwood , peter@chubb.wattle.id.au, linux-kernel@vger.kernel.org Subject: Re: stat very inefficient Message-ID: <20040729002924.GK12308@parcelfarce.linux.theplanet.co.uk> References: <233602095@toto.iv> <16648.10711.200049.616183@wombat.chubb.wattle.id.au> <20040728154523.20713ef1.davem@redhat.com> <20040729000837.GA24956@taniwha.stupidest.org> <20040728171414.5de8da96.davem@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040728171414.5de8da96.davem@redhat.com> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 28, 2004 at 05:14:14PM -0700, David S. Miller wrote: > On Wed, 28 Jul 2004 17:08:37 -0700 > Chris Wedgwood wrote: > > > Just How bad is it for you? I just tested stat on my crapbox and for > > a short path 1M stats takes 0.5s and for a longer path (30 bytes or > > so) 2.8s. > > Run "time find . -type f" on the kernel tree, both before and > after removing the third unnecessary copy. ... with hot cache, otherwise IO time will dominate. I don't disagree with you, but in all realistic cases I can think of it's going to be noise (e.g. this find over kernel tree is almost certainly followed by xargs grep, etc.).