From mboxrd@z Thu Jan 1 00:00:00 1970 From: Richard Scobie Subject: Re: SAS v SATA interface performance Date: Sun, 02 Dec 2007 12:55:46 +1300 Message-ID: <4751F482.60204@clear.net.nz> References: <47506237.3000406@clear.net.nz> <47507F9A.3080109@msgid.tls.msk.ru> <20071130231705.51e056f4@the-village.bc.nu> <475110A8.5090709@clear.net.nz> <87f94c370712010637o5efa9c4rd9a86ec5a3cba6ff@mail.gmail.com> <4751B3DA.6030508@clear.net.nz> <4751BDA4.9080102@rtr.ca> <4751C6DA.3080409@garzik.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from smtp.sauce.co.nz ([210.48.49.72]:37119 "EHLO smtp.sauce.co.nz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752522AbXLAX5A (ORCPT ); Sat, 1 Dec 2007 18:57:00 -0500 In-Reply-To: <4751C6DA.3080409@garzik.org> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Jeff Garzik Cc: Mark Lord , linux-ide@vger.kernel.org Jeff Garzik wrote: > Mark Lord wrote: >> SATA port multipliers (think, "hub") permit multiple drives >> to be active simultaneously. > > Quite true, although the host controller could artificially limit this, > giving the user a mistaken impression of their port multiplier being > limited to one-command-per-N-drives. Interesting. I was basing my comments on what may well be a vested interest slanted paper - see the sidebar on page 2. http://www.xtore.com/Downloads/WhitePapers/SAS_SATAValue%20Whitepaper_final.pdf For the modest extra cost of a non-RAID SAS HBA and JBOD enclosure with SATA drives, over a port multiplied setup, there would seem to be some advantages. Or have I been taken in by the hype... :) Regards, Richard