From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 25 Jan 2001 15:29:03 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 25 Jan 2001 15:28:53 -0500 Received: from vega.digitel2002.hu ([213.163.0.181]:7690 "EHLO vega.digitel2002.hu") by vger.kernel.org with ESMTP id ; Thu, 25 Jan 2001 15:28:33 -0500 Date: Thu, 25 Jan 2001 21:28:25 +0100 From: Gábor Lénárt To: Thunder from the hill Cc: linux-kernel@vger.kernel.org Subject: Re: vfat <-> vfat copying of ~700MB file, so slow! Message-ID: <20010125212825.B23684@vega.digitel2002.hu> In-Reply-To: <20010124131431.A19957@ikar.t17.ds.pwr.wroc.pl> <997u6tsn18dp9u1h97q4j5jc9a2amn1nsp@i-vic.net> <20010124193525.A28379@ikar.t17.ds.pwr.wroc.pl> <3A7076E3.D9E6AF8B@ngforever.de> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit User-Agent: Mutt/1.3.12i In-Reply-To: <3A7076E3.D9E6AF8B@ngforever.de>; from thunder@ngforever.de on Thu, Jan 25, 2001 at 11:56:35AM -0700 X-Operating-System: vega Linux 2.2.18 i686 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 25, 2001 at 11:56:35AM -0700, Thunder from the hill wrote: > Arkadiusz Miskiewicz wrote: > > > > On/Dnia Wed, Jan 24, 2001 at 12:23:03PM -0600, Brad Felmey wrote/napisa?(a) > > > > I/O support = 0 (default 16-bit) > > > > > > hdparm -c1 /dev/hda, or are you running in 16-bit mode on purpose? > > no purpose. Setting this can only speed up all operations a bit but it doesn't > > change nothing in vfat <-> vfat copying. It still slows down while copying. > I noticed the kernel to increase cache and let the buffers break down during long file copies, it seems like this is the wrong way if only copying one large file. This also happens on SMB connections. I don't know if this info is useful. Hmmm, imho this is a more general problem. Of course kernel does not know if this is a single copy or data should be cached since it will be used frequently in the near future. I don't know kernel internals very well but I think cache is block cache. On higher layer (fs) it would be possible to check out that we simply read blocks of file linear (which means something like you mentioned especially on big files). I met similar problems when I copy a harddisk to another (same type), with simple dd'ing /dev/hda to /dev/hdb. Even with 192Mbs of RAM, the system goes down to a very uninteractive state :( This copy task may be implemented on raw devices to avoid caching nowdays. Please correct me, because these are only feelings or what :) -- --[ Gábor Lénárt ]---[ Vivendi Telecom Hungary ]--[ lgb@supervisor.hu ]-- U have 8 bit comp or chip of them and it's unused or to be sold? Call me! -------[ +36 30 2270823 ]------> LGB <-----[ Linux/UNIX/8bit 4ever ]----- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/