From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932488Ab2LFKgk (ORCPT ); Thu, 6 Dec 2012 05:36:40 -0500 Received: from mail-ie0-f175.google.com ([209.85.223.175]:61582 "EHLO mail-ie0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932143Ab2LFKgj (ORCPT ); Thu, 6 Dec 2012 05:36:39 -0500 X-Greylist: delayed 1644 seconds by postgrey-1.27 at vger.kernel.org; Thu, 06 Dec 2012 05:36:39 EST Message-ID: <50C06EC3.20002@redhat.com> Date: Thu, 06 Dec 2012 11:09:07 +0100 From: Paolo Bonzini User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: "Kirill A. Shutemov" CC: "James E.J. Bottomley" , Matthew Wilcox , Tim Chen , linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] scsi_ram: a RAM-based SCSI driver References: <1354725918-14713-1-git-send-email-kirill.shutemov@linux.intel.com> In-Reply-To: <1354725918-14713-1-git-send-email-kirill.shutemov@linux.intel.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Il 05/12/2012 17:45, Kirill A. Shutemov ha scritto: > From: "Kirill A. Shutemov" > > This driver is intended to run as fast as possible, hence the options to > discard writes and reads. It's designed to let us find latency issues > elsewhere in the storage stack (eg filesystem, block layer, scsi layer). > > There are a few different options, controlled through module parameters. > The sector size and disc capacity are load-time parameters, but the > parameters affecting performance are tweakable at runtime. > > By default, it'll allocate half a gigabyte of RAM to use as a ramdisc; > you can change this with the `capacity' module parameter. Is this that much faster than scsi-debug? The discarding options surely can be added there. Paolo