From owner-freebsd-questions@FreeBSD.ORG Tue Jun 10 22:10:34 2008 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id D41EF1065676 for ; Tue, 10 Jun 2008 22:10:34 +0000 (UTC) (envelope-from wojtek@wojtek.tensor.gdynia.pl) Received: from wojtek.tensor.gdynia.pl (wojtek.tensor.gdynia.pl [IPv6:2001:4070:101:2::1]) by mx1.freebsd.org (Postfix) with ESMTP id CF37C8FC15 for ; Tue, 10 Jun 2008 22:10:33 +0000 (UTC) (envelope-from wojtek@wojtek.tensor.gdynia.pl) Received: from wojtek.tensor.gdynia.pl (localhost [IPv6:::1]) by wojtek.tensor.gdynia.pl (8.14.2/8.14.2) with ESMTP id m5AMAV1K013115; Wed, 11 Jun 2008 00:10:31 +0200 (CEST) (envelope-from wojtek@wojtek.tensor.gdynia.pl) Received: from localhost (wojtek@localhost) by wojtek.tensor.gdynia.pl (8.14.2/8.14.2/Submit) with ESMTP id m5AMATSf013112; Wed, 11 Jun 2008 00:10:31 +0200 (CEST) (envelope-from wojtek@wojtek.tensor.gdynia.pl) Date: Wed, 11 Jun 2008 00:10:29 +0200 (CEST) From: Wojciech Puchar To: Erik Trulsson In-Reply-To: <20080610193742.GA68256@owl.midgard.homeip.net> Message-ID: <20080611000741.P13017@wojtek.tensor.gdynia.pl> References: <484EACEB.7169.43FE1258@iwrtech.iwr.ru.ac.za> <20080610165435.M68290@wojtek.tensor.gdynia.pl> <20080610150536.GA67056@owl.midgard.homeip.net> <20080610171129.K75322@wojtek.tensor.gdynia.pl> <20080610193742.GA68256@owl.midgard.homeip.net> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: freebsd-questions@freebsd.org, DA Forsyth Subject: Re: xRAID disks.... X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 10 Jun 2008 22:10:34 -0000 > You do not normally have that much bandwidth even in a modern machine. > Typical bandwidth for the northbridge/southbridge connection is 1-2 GB/s > for most machines sold today. (For example just about all machines with > a recent Intel desktop chipset. The connection between north- and south-bridge > on those is equivalent to a PCI-E x4 connection (which provides 1GB/s in each > direction.)) as long as it's not saturated it's not a problem. >>> with several other devices (which is not uncommon) then the reduced >>> bandwidth usage can be very useful. >> >> true. but not if it's builtin in chipset or on PCI express. > > PCI-E controller cards are still fairly uncommon, and many of them but integrated in chipset - common. > require a x4 or x8 slot, while most motherboards only have x1 slots > (apart from the x16 slot intended for a graphics card.) this slot is usable for anything. i always take some old PCI card for free for servers. as they don't need graphics anyway. on my 8-disk server i could get 95MB/s from EACH of 8 drives in parallel, still having minimal system load. it isn't anything expensive, quite cheap gigabyte motherboard with core2 duo and 2GB RAM