From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Bottomley Subject: Re: queue depth help!! Date: 27 Dec 2003 15:46:32 -0600 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <1072561593.1757.48.camel@mulgrave> References: <3FF514CE@webmail.colostate.edu> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from stat1.steeleye.com ([65.114.3.130]:33940 "EHLO hancock.sc.steeleye.com") by vger.kernel.org with ESMTP id S264605AbTL0Vql (ORCPT ); Sat, 27 Dec 2003 16:46:41 -0500 In-Reply-To: <3FF514CE@webmail.colostate.edu> List-Id: linux-scsi@vger.kernel.org To: jshankar Cc: linux-scsi On Sat, 2003-12-27 at 15:38, jshankar wrote: > if the scsi target queue depth is 1, does it mean that i can handle only one > outstanding command at a time. Yes > Does it mean if another command is issued( queue depth=1), it has to wait till > the previous command is done. Yes. The mid-layer will start the queued command as soon as the one occupying the device returns...this is often why untagged devices actually set their depth to 2 so they can have another command all prepared and ready to roll as soon as the in-progress one returns. James