From owner-freebsd-fs@FreeBSD.ORG Sun Apr 14 10:01:49 2013 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by hub.freebsd.org (Postfix) with ESMTP id 1983AFD for ; Sun, 14 Apr 2013 10:01:49 +0000 (UTC) (envelope-from mxb@alumni.chalmers.se) Received: from mail-la0-x232.google.com (mail-la0-x232.google.com [IPv6:2a00:1450:4010:c03::232]) by mx1.freebsd.org (Postfix) with ESMTP id 937BA91A for ; Sun, 14 Apr 2013 10:01:47 +0000 (UTC) Received: by mail-la0-f50.google.com with SMTP id el20so3610308lab.37 for ; Sun, 14 Apr 2013 03:01:47 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-received:from:content-type:message-id:mime-version:subject:date :references:to:in-reply-to:x-mailer:x-gm-message-state; bh=GogMaD4af4lbIF2SZ9kNpDyuew42Dp46GxgGi+0An+w=; b=CH54ddnEl6QQ72eU0yhaEUsr6HASvTIpdAdetxc2AkxXeAV55nX5LmMj2dycHyjBsF vGZ+ES94wPywgf7Ni1VF7otx0q5zjoL8P7dW6ElXT1XkgwQZeu4FxLDNH+ayDapQwMVM is5OOgidf8hwjusbYoodxSYPVyyTMrzz9pRXS0N/bbIbcqTA16va8zhQEgCqM+30uj3O DoI111oMQoRjhUYOlFvWXU7B1RJjwS86XkQPVz6FylRLcCFJa7GEt1zPX75ZpZ9UTA1d yN5auz/xUOGiCdujAXjjS4knCbDOrYVC5poTITsigltJ4xASIT2ipUAsLg5FPULfV+fW pgTw== X-Received: by 10.112.173.39 with SMTP id bh7mr8339980lbc.62.1365933706960; Sun, 14 Apr 2013 03:01:46 -0700 (PDT) Received: from grey.home.unixconn.com (h-74-23.a183.priv.bahnhof.se. [46.59.74.23]) by mx.google.com with ESMTPS id xx3sm6016793lbb.14.2013.04.14.03.01.45 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Sun, 14 Apr 2013 03:01:46 -0700 (PDT) From: mxb Message-Id: <9EE9328B-40B1-4510-B404-242D0F2C7697@alumni.chalmers.se> Mime-Version: 1.0 (Mac OS X Mail 6.3 \(1503\)) Subject: Re: ZFS: ZIL device export/import Date: Sun, 14 Apr 2013 12:01:43 +0200 References: <5A2824CA-2A67-47FA-AB27-20C6EBD2C501@alumni.chalmers.se> <51699B8E.7050003@platinum.linux.pl> <2DE8AD5E-B84C-4D88-A242-EA30EA4A68FD@alumni.chalmers.se> To: "freebsd-fs@freebsd.org" In-Reply-To: X-Mailer: Apple Mail (2.1503) X-Gm-Message-State: ALoCoQlY+dacN1cAzXKb6xhmxlpsWUCSOaFyloiV1ajIdog5lbLYRy5FSlYkNG4Qiety2/xtwNSY Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.14 X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 14 Apr 2013 10:01:49 -0000 Well, I'm trying to preclude any undesired effect in the whole setup, as = this is going to production. SAS-link might not be a bottleneck here and I'm overreacting. Locally ,on per HU basis, I have 6Gbit/s SAS/SATA. Both card and = disks(SSD) attached to it. SAS Expander is also 6Gbit/s, attaching 10k RPM SAS mechanical disks on = JBOD. I use Intel 520 SSD and Pulsar SSD in this setup. ZIL resided locally on Intel SSD(per HU), but now will probably move to = Pulsar SSD(moved to JBOD as those disks have dual SAS/SATA link). L2ARC = resided on Pulsar (Pulsar was in each HU. eg. I have 2x Pulsar). Looks like I have to re-design the whole setup, as of ZIL. //mxb On 13 apr 2013, at 22:51, Ronald Klop = wrote: > I thought the idea of ZIL is a fast buffer before the write to slow = disk. Are you really sure the SAS expander is the bottleneck in the = system instead of the disks?