From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752120Ab1GXB5B (ORCPT ); Sat, 23 Jul 2011 21:57:01 -0400 Received: from one.firstfloor.org ([213.235.205.2]:58732 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751795Ab1GXB4y (ORCPT ); Sat, 23 Jul 2011 21:56:54 -0400 Date: Sun, 24 Jul 2011 03:56:52 +0200 From: Andi Kleen To: "J. Bruce Fields" Cc: Matt Mackall , NeilBrown , Andi Kleen , linux-fsdevel , Linux Kernel Mailing List Subject: Re: Nanosecond fs timestamp support: sad Message-ID: <20110724015652.GX8006@one.firstfloor.org> References: <20110722163335.2df4f6ca@notabene.brown> <1311363269.14555.261.camel@calx> <20110722205922.GS8006@one.firstfloor.org> <1311369102.14555.268.camel@calx> <20110722214732.GW8006@one.firstfloor.org> <20110722221039.GB10749@fieldses.org> <20110722223158.GC10749@fieldses.org> <20110723085915.308ddc02@notabene.brown> <1311379661.20898.23.camel@calx> <20110723013809.GA12174@fieldses.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110723013809.GA12174@fieldses.org> User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > with a stat. So either you have a clock good enough to give a distinct > timestamp for all of those, or you fall back on a global counter that > ends up serializing all IO. I think. I admit I'm not sure I understand Not global counter, but per inode. That's very reasonable because there's already locking on the inode level. -Andi