From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933728AbYD1MNX (ORCPT ); Mon, 28 Apr 2008 08:13:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1765374AbYD1MNL (ORCPT ); Mon, 28 Apr 2008 08:13:11 -0400 Received: from accolon.hansenpartnership.com ([76.243.235.52]:38716 "EHLO accolon.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1765110AbYD1MNJ (ORCPT ); Mon, 28 Apr 2008 08:13:09 -0400 Subject: Re: [GIT PATCH] another tranche of SCSI updates for 2.6.26 From: James Bottomley To: Boaz Harrosh Cc: Ingo Molnar , Andrew Morton , Linus Torvalds , linux-scsi , linux-kernel In-Reply-To: <48157B6A.60307@panasas.com> References: <1209320076.3801.26.camel@localhost.localdomain> <20080428013400.GA6245@elte.hu> <1209351113.3801.107.camel@localhost.localdomain> <48157B6A.60307@panasas.com> Content-Type: text/plain Date: Mon, 28 Apr 2008 08:13:03 -0400 Message-Id: <1209384784.3367.1.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.12.3 (2.12.3-4.fc8) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2008-04-28 at 10:23 +0300, Boaz Harrosh wrote: > If we are already on the subject. It looks like we always have at most 1 command in the > free list, so why the free list at all? or am I reading the code wrong? Because list handlers are well understood mechanisms within the kernel. Also because in low memory situations, one command per host is sufficient to guarantee forward progress, but it's not going to be very efficient. Embedded and other low memory environments can increase the size of the free list to improve their I/O path. James