From owner-freebsd-stable@FreeBSD.ORG Tue Jun 7 08:35:58 2011 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id AB4E01065670 for ; Tue, 7 Jun 2011 08:35:58 +0000 (UTC) (envelope-from mavbsd@gmail.com) Received: from mail-fx0-f54.google.com (mail-fx0-f54.google.com [209.85.161.54]) by mx1.freebsd.org (Postfix) with ESMTP id 34A8F8FC14 for ; Tue, 7 Jun 2011 08:35:57 +0000 (UTC) Received: by fxm11 with SMTP id 11so4367166fxm.13 for ; Tue, 07 Jun 2011 01:35:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:sender:message-id:date:from:user-agent :mime-version:to:subject:references:in-reply-to:content-type :content-transfer-encoding; bh=rc+p5trwSJ8csOsS3h1PqrppqEiehGP2FpL3mFDXIWk=; b=N0v6UWc/UzoY7uSvMEwLj1yJzGD4Pct5V6+BvzEw+XNAAge0zAp31ZMPjCRPYpPqE9 Gz6aDCdxxn4kiFSot/m9r05uwNSXkEPfL6SeVPJfDtQ4ayWp9BISndkpdyXNjncKKlHq waLBZgD8AY3vbzNMG5nuuZwV5Fy2fX9Y5hLv4= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:message-id:date:from:user-agent:mime-version:to:subject :references:in-reply-to:content-type:content-transfer-encoding; b=Ba0Ws1a9HI3ejd/mMm3m9dnuSUvr9Hh8TVHqei/E1zqTL82LpNHP6KLcbe7/1rzmT5 e8bu2jUNF11H9xeewDWlVrr3vom0AVpINKnM/vevOqX65mC00CDDVbIiR2qHeMIPzXKg QdAQLjU1YT379PJFpnWz4SL93Qb6qDUKPp5bs= Received: by 10.223.57.5 with SMTP id a5mr3642506fah.90.1307435757009; Tue, 07 Jun 2011 01:35:57 -0700 (PDT) Received: from mavbook.mavhome.dp.ua (pc.mavhome.dp.ua [212.86.226.226]) by mx.google.com with ESMTPS id e16sm1627599fak.41.2011.06.07.01.35.55 (version=SSLv3 cipher=OTHER); Tue, 07 Jun 2011 01:35:56 -0700 (PDT) Sender: Alexander Motin Message-ID: <4DEDE2E5.6080406@FreeBSD.org> Date: Tue, 07 Jun 2011 11:35:49 +0300 From: Alexander Motin User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-US; rv:1.9.2.15) Gecko/20110310 Thunderbird/3.1.9 MIME-Version: 1.0 To: FreeBSD Stable References: In-Reply-To: Content-Type: text/plain; charset=KOI8-R; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: PCIe SATA HBA for ZFS on -STABLE X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 07 Jun 2011 08:35:58 -0000 On 07.06.2011 05:33, Matthew Dillon wrote: > The absolute cheapest solution is to buy a Sil-3132 PCIe card > (providing 2 E-SATA ports), and then connect an external port multiplier > to each port. External port multiplier enclosures typically support > 5 drives each so that would give you your 10 drives. > > Even the 3132 is a piss-ant little card it does support FIS-Based > switching so performance will be very good... it will just be limited > to SATA-II speeds is all. SiI3132 is indeed good for it's price and it is quite good for random I/O. But at burst speeds it is limited lower then SATA-II. Even lower then PCIe 1.0 x1 it uses. IIRC I've seen about 150MB/s from one port and about 170MB/s from two. If burst rate is important, SiI3124 chip is much better -- up to about 900MB/s measured from 4 ports. The only issue is PCI-X interface: either motherboard with PCI-X needed, or card with PCIe x8 bridge (like these http://www.addonics.com/products/host_controller/adsa3gpx8-4e.asp), but last case is too expensive. There are also much cheaper (~$50) PCIe x1 bridge SiI3124 cards (http://www.sybausa.com/productInfo.php?iid=537). They are not so fast -- about 200MB/s, but still more then SiI3132. And they still have 4 SATA ports. > For SSDs you want to directly connect the SSD to a mobo SATA port and > then either mount the SSD in the case or mount it in a hot-swap gadget > that you can screw into a PCI slot (it doesn't actually use the PCI > connector, just the slot). A SATA-III port with a SATA-III SSD really > shines here and 400-500 MBytes/sec random read performance from a single > SSD is possible, but it isn't an absolute requirement. A SATA-II port > will still work fine as long as you don't mind maxing out the bandwidth > at 250 MBytes/sec. Agree. Intel on-board ports rock! Recently I've built new system with two OCZ Vertex 3 SSDs connected to 6Gbps SATA ports on Intel Sandy Bridge class motherboard. UFS on top of graid RAID0 volume gives me about 950MB/s on both read and write! > To get robust hot-swap enclosures you either need to go with SAS or you > need to go with discrete SATA ports (no port multiplication), and the > ports have to support hot-swap. The best hot-swap support for an AHCI > port is if the AHCI chipset supports cold-presence-detect (CPD), and > again Mobo AHCI chipsets usually don't. Hot-swap is a bit hit or miss > without CPD because power savings modes can effectively prevent hot-swap > detect from working properly. Drive disconnects will always be detected > but drive connects might not be. I would say it depends. In some cases it is easier to detect hot-plug then hot-unplug, as device sends COMINIT that should wake up port even from power-save state. With ICH10, for example, I've managed to make both hot plug and unplug work even with power-management enabled: hot-plug via tracking COMINIT, unplug via it's CPD capability. Without PM it "just works". :) -- Alexander Motin