From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Freemyer Subject: Re: GPT fdisk Date: Fri, 16 Apr 2010 16:11:05 -0400 Message-ID: References: <721544.69241.qm@web95511.mail.in.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Return-path: Received: from mail-pw0-f46.google.com ([209.85.160.46]:45237 "EHLO mail-pw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932317Ab0DPULG convert rfc822-to-8bit (ORCPT ); Fri, 16 Apr 2010 16:11:06 -0400 Received: by pwj9 with SMTP id 9so2316568pwj.19 for ; Fri, 16 Apr 2010 13:11:05 -0700 (PDT) In-Reply-To: <721544.69241.qm@web95511.mail.in.yahoo.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: "Keshav P.R." Cc: tj@kernel.org, linux-ide@vger.kernel.org On Fri, Apr 16, 2010 at 2:06 PM, Keshav P.R. wrote: > Hi, I am Keshav from India. I read https://ata.wiki.kernel.org/index.php/ATA_4_KiB_sector_issues page which was very informative. I currently do not have any 4K sector drives but regarding GPT-4K sector support, check out this software http://rodsbooks.com/gdisk/ . This is currently the best GPT software (which is also cross-platform). > > I also have a question :- If I have a 4K sector internal HDD (without any jumpers etc. ie. the drive shows itself as 4K logical sector size), will there be any difference in behaviour of linux with these drives with respect to Legacy-IDE SATA mode and AHCI SATA mode options available in the BIOS ? Thank you. Keshev, To the best of my knowledge, no 4K logical sector drives exist yet and they may not for some time (ie. years??), so I don't think your question can be answered. Specifically, I don't believe there are any drives regardless of jumpers that enable a 4K presentation on the sata bus. All bus communications are based on 512 byte sectors. And all addressing is based on 512 byte sectors. Thus they appear to the bios to be standard 512 byte sector drives and the bios has no interaction issues. The reality that a physical 4K sector is actually being manipulated on the drive platters is a performance issue. And thus it is important to align filesystem 4K blocks with the drives physical 4K sectors to avoid an excessive amount of read / modify / write activity within the drive controller electronics. Greg