From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vladislav Bolkhovitin Subject: Re: [ANNOUNCE] iSCSI enterprise target software Date: Wed, 02 Mar 2005 13:47:26 +0300 Message-ID: <422599BE.9020008@vlnb.net> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Received: from smtpout.azz.ru ([81.176.69.27]:31682 "HELO mailserver.azz.ru") by vger.kernel.org with SMTP id S262257AbVCBKof (ORCPT ); Wed, 2 Mar 2005 05:44:35 -0500 In-Reply-To: Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Bryan Henderson Cc: Arjan van de Ven , FUJITA Tomonori , iscsitarget-devel@lists.sourceforge.net, linux-scsi@vger.kernel.org Bryan Henderson wrote: >>You want to *use* the kernel pagecache as much as you can. > > > No, I really don't. Not always. I can think of only 2 reasons to > maximize my use of the kernel pagecache: 1) saves me duplicating code; 2) > allows me to share resources (memory and disk bandwidth come to mind) with > others in the same Linux system fairly. There are many cases where those > two benefits are outweighed by the benefits of using some other cache. If > you're thinking of other benefits of using the pagecache, let's hear them. You forgot the third reason (benefit), though it doesn't directly related to the page cache: read ahead. It greatly influences on the performance and a direct I/O application has to reimplement this logic, which generally isn't straightforward task. Vlad