From mboxrd@z Thu Jan 1 00:00:00 1970 From: Saswat Praharaj Subject: read vs write Date: Mon, 25 Jul 2005 15:44:27 +0530 Message-ID: Reply-To: Saswat Praharaj Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Return-path: Received: from wproxy.gmail.com ([64.233.184.204]:64831 "EHLO wproxy.gmail.com") by vger.kernel.org with ESMTP id S261185AbVGYKO2 convert rfc822-to-8bit (ORCPT ); Mon, 25 Jul 2005 06:14:28 -0400 Received: by wproxy.gmail.com with SMTP id i1so956498wra for ; Mon, 25 Jul 2005 03:14:27 -0700 (PDT) Content-Disposition: inline Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: linux-ide@vger.kernel.org Hello Experts, I am a kernel newbie. While checking the hard-disk performance I have found that write is significantly slower than read. In my setup I am using UDMA 5 mode , and I am using is ST340016A (from Seagate) and Diamond Max Plus 9 (from Maxtor). I checked the product manual for ST340016A and found that seek time for read/write is approximately same. While, I am able to read at a speed of 55 Mbps , for write operation the speed decreases to 20Mbps. I am using linux kernel version 2.4.25 #41 . Can anyone give me some info on why write is so slow compared to read. Moreover, I am wondering if I could achieve the 100Mbps read speed as claimed by different vendors.For me , It should ideally be 100 Mbps as I am using a 80 conductor cable and UDMA 5.Why then I am getting 58 Mbps max . . Is it because linux kernel 2.4.25 supports upto ATA-2 standard ?? Well, I am using a 400 MHz amd processor. I would greatly appreciate if some one could explain the read/write behaviour and help me find out how can I get 100 Mbps speed . Thanks for reading my mail. Regards, -Saswat