From owner-freebsd-fs@FreeBSD.ORG Wed Apr 17 21:43:16 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 AB3B37B8 for ; Wed, 17 Apr 2013 21:43:16 +0000 (UTC) (envelope-from mxb@alumni.chalmers.se) Received: from mail-la0-x231.google.com (mail-la0-x231.google.com [IPv6:2a00:1450:4010:c03::231]) by mx1.freebsd.org (Postfix) with ESMTP id 31E3092E for ; Wed, 17 Apr 2013 21:43:16 +0000 (UTC) Received: by mail-la0-f49.google.com with SMTP id fs13so1204250lab.36 for ; Wed, 17 Apr 2013 14:43:15 -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=zzqy0WXuz+U2GqljW1+Rix3X0YNycdeAfZ1lpxlQ9Dk=; b=ciT6k6eZ2V8w95ZYHjA8LyBj43eQ8VnXFkyDPluGMy9R20jlodIzMwr7GKzC6ic+3O Iv96Av57CxHuXAgqK04oQbC0hGVpMLpKbNIDe2z1gGWxo3fF46JbltrN5C4GdFkVT3Oz LCIqWQtcKLc3K8MXcLkmCguyQv/KdHG8vVzm3qahr1Qk7KSf/KjSGW4RHFVukrF+G//c WKx2fmJ4o14XhzGju/WRg6bxVrMqHDa8XPUrUryXoXksrk3SQuRFswMthz+jcbG/cKCQ +hdtVcI+Idnq1Io2LoSdPpN0jfP7qED5TfvqhSPGBVquguIWu+5D9R+T3HisOV7CcBno i2ww== X-Received: by 10.152.3.4 with SMTP id 4mr4411435lay.29.1366234994857; Wed, 17 Apr 2013 14:43:14 -0700 (PDT) Received: from grey.home.unixconn.com (h-75-17.a183.priv.bahnhof.se. [46.59.75.17]) by mx.google.com with ESMTPS id y9sm3301246lae.10.2013.04.17.14.43.13 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 17 Apr 2013 14:43:13 -0700 (PDT) From: mxb Message-Id: <2753912E-0B91-4F73-B956-9D558F16EEAE@alumni.chalmers.se> Mime-Version: 1.0 (Mac OS X Mail 6.3 \(1503\)) Subject: Re: ZFS: ZIL device export/import Date: Wed, 17 Apr 2013 23:43:11 +0200 References: <5A2824CA-2A67-47FA-AB27-20C6EBD2C501@alumni.chalmers.se> <51699B8E.7050003@platinum.linux.pl> <2DE8AD5E-B84C-4D88-A242-EA30EA4A68FD@alumni.chalmers.se> <9EE9328B-40B1-4510-B404-242D0F2C7697@alumni.chalmers.se> To: "freebsd-fs@freebsd.org" In-Reply-To: <9EE9328B-40B1-4510-B404-242D0F2C7697@alumni.chalmers.se> X-Mailer: Apple Mail (2.1503) X-Gm-Message-State: ALoCoQmzQcwJKbfFRUFR+2d3+nD7u5N/FYki3cxnDhP/r8lYsxzw8LPfYp+GYxrnCod04OwxTthf 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: Wed, 17 Apr 2013 21:43:16 -0000 Thanks everyone, whom replied! //mxb On 14 apr 2013, at 12:01, mxb wrote: >=20 > Well, I'm trying to preclude any undesired effect in the whole setup, = as this is going to production. >=20 > SAS-link might not be a bottleneck here and I'm overreacting. >=20 > 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. >=20 > 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). >=20 > Looks like I have to re-design the whole setup, as of ZIL. >=20 > //mxb >=20 >=20 > On 13 apr 2013, at 22:51, Ronald Klop = wrote: >=20 >> 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? >=20