From owner-freebsd-stable@FreeBSD.ORG Tue May 29 21:00:02 2012 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 79CDB1065675; Tue, 29 May 2012 21:00:02 +0000 (UTC) (envelope-from kjkoster@gmail.com) Received: from mail-wg0-f50.google.com (mail-wg0-f50.google.com [74.125.82.50]) by mx1.freebsd.org (Postfix) with ESMTP id CC9388FC16; Tue, 29 May 2012 21:00:01 +0000 (UTC) Received: by wgbds11 with SMTP id ds11so4330759wgb.31 for ; Tue, 29 May 2012 14:00:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=subject:mime-version:content-type:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to:x-mailer; bh=IwABZuM19JuuLkZJT05XJET38SPgu++wQOzKK7V+Wec=; b=n7sRDsSHGj6ericfwfqx+URFDrPuCbvadB4q3YfdIoKKYVYKxMKsA7alvmGFW3/jmy Q9/7+G9D0yY6X7HT0K5D9yWQ0yaiGkfbP06TiXKtccTJwfMlkyqQpsLntMY6/Ok1bWZq VPxLMyHhsubcSgJe6Bl8EDRidLYr8FxRqO7v3pg9Xse8cgE52lvaYvG27TGll9vHYwcL A+91eUcCSdYAlGWGbTQiW3qDsb7WhYuHeCarrCWg8vd44K1mT/0hxORenZkK7L60s24h ezB6nhlKJGYLjJxuA0YltiUacMv/xoRQOzGX6wcIfmtPI+HAvMO0mm2GeNSbl2/LTt8V w74A== Received: by 10.216.145.149 with SMTP id p21mr8661697wej.1.1338325200622; Tue, 29 May 2012 14:00:00 -0700 (PDT) Received: from kees-jan-kosters-macbook-air.fritz.box (kjkoster.org. [83.163.197.206]) by mx.google.com with ESMTPS id hv7sm44250239wib.0.2012.05.29.13.59.59 (version=TLSv1/SSLv3 cipher=OTHER); Tue, 29 May 2012 14:00:00 -0700 (PDT) Mime-Version: 1.0 (Apple Message framework v1278) Content-Type: text/plain; charset=us-ascii From: Kees Jan Koster In-Reply-To: <20120529203913.GB92444@in-addr.com> Date: Tue, 29 May 2012 22:59:58 +0200 Content-Transfer-Encoding: quoted-printable Message-Id: <43F6FDD2-3D31-44D7-82C7-4466D609ECF2@gmail.com> References: <20120529203913.GB92444@in-addr.com> To: Gary Palmer X-Mailer: Apple Mail (2.1278) Cc: freebsd-stable@freebsd.org Subject: Re: FreeBSD 9.0 hangs on heavy I/O 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, 29 May 2012 21:00:02 -0000 Dear Gary, >> # camcontrol devlist >> at scbus1 target 0 lun 0 = (pass0,ada0) >> at scbus2 target 0 lun 0 = (pass1,ada1) >> at scbus3 target 0 lun 0 = (pass2,ada2) >> at scbus4 target 0 lun 0 = (pass3,ada3) >> at scbus7 target 0 lun 0 = (pass4,cd0) >> at scbus8 target 0 lun 0 = (pass5,cd1) >=20 > Check the SSD for its internal block size and make sure your = filesystem > and partitions are aligned with the disk block size. Unless there > is something wrong with your SATA controller I'd expect a lot more = than > 273 IOPS/sec and ~30MByte/sec from a SSD. Thank you for suggesting this. However, I recently went through my file = systems to fix disk alignment. I ended up aligning them to 1M blocks, = which raised the throughput from 6M/s to about 60-80MB/s which is what I = am seeing today. # gpart show ... =3D> 34 250069613 ada3 GPT (119G) 34 2014 - free - (1M) 2048 250067599 1 freebsd-ufs (119G) Do you think I need to revisit alignment? -- Kees Jan http://java-monitor.com/ kjkoster@kjkoster.org +31651838192 Change is good. Granted, it is good in retrospect, but change is good.