From owner-freebsd-fs@FreeBSD.ORG Wed Jan 9 03:58:53 2013 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id 15BBE571; Wed, 9 Jan 2013 03:58:53 +0000 (UTC) (envelope-from fjwcash@gmail.com) Received: from mail-la0-f50.google.com (mail-la0-f50.google.com [209.85.215.50]) by mx1.freebsd.org (Postfix) with ESMTP id 2E4FAF00; Wed, 9 Jan 2013 03:58:51 +0000 (UTC) Received: by mail-la0-f50.google.com with SMTP id fs13so1322109lab.37 for ; Tue, 08 Jan 2013 19:58:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=3kCk7NbkyFZLdl9y/ydUHv9P4u1An5JOpw2yk3CGChQ=; b=p1QzZsp2SFyvV27fwghGjkJOI9g4K4WQuVuTh2DeeEx1Ms3fiCteYerj3f7K0leMfX /ZCX0OeCuAnIcPzWnfgp+gFd2bB2tDi29vvMGEs6iWKPSilOYuk5Hv7AJMmp4NjvJ/jq R9bFgcIAvFSzUSwMJhrmqhad9jHi9RDFC9DF08qkBDKxA9wXcsTOLN+Q7R9kK4Es5iAa s+FIFKtJLYnWR+E3S5GNWkLCCBGVvyLQeaSuWBQKB3SXprD2yGFyujMY4ZgkKYkQAtIA mk/QrPK0LSBNUUfD8LjzgeIcLT8icYpA4n330vRKsAsoTXnUxZ2bt0c0D0BrpEnPkSDK Cbxg== MIME-Version: 1.0 Received: by 10.112.39.129 with SMTP id p1mr27375481lbk.26.1357703930563; Tue, 08 Jan 2013 19:58:50 -0800 (PST) Received: by 10.114.81.40 with HTTP; Tue, 8 Jan 2013 19:58:50 -0800 (PST) Received: by 10.114.81.40 with HTTP; Tue, 8 Jan 2013 19:58:50 -0800 (PST) In-Reply-To: <20130109031834.GA14386@FreeBSD.org> References: <20130109023327.GA1888@FreeBSD.org> <20130109.115240.1198411557684741197.hrs@allbsd.org> <20130109031834.GA14386@FreeBSD.org> Date: Tue, 8 Jan 2013 19:58:50 -0800 Message-ID: Subject: Re: rc.d script for memory based zfs intent log From: Freddie Cash To: John Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.14 Cc: FreeBSD Filesystems 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, 09 Jan 2013 03:58:53 -0000 On Jan 8, 2013 7:18 PM, "John" wrote: > > ----- Hiroki Sato's Original Message ----- > > John wrote > > in <20130109023327.GA1888@FreeBSD.org>: > > > > jw> Hi Folks, > > jw> > > jw> Here's an rc.d script that provides a nice performance boost on > > jw> ZFS/NFS based file servers. It also helps in other areas not specific > > jw> to NFS. > > jw> > > jw> It attaches the log device at system startup and removes it at > > jw> system shutdown time. Example; > > jw> > > jw> memzil_pools="tank" > > jw> memzil_bootfs="YES" > > jw> service memzil onestart > > jw> zpool status tank > > jw> service memzil onestop > > jw> > > jw> This configuration provides a nice performance boost especially to > > jw> NFS, but also helps in other areas not specific to NFS. > > jw> > > jw> Please DO NOT USE this script if your system is not UPS backed, preferably > > jw> with dual power supplies on separate circuits. If your system crashes you > > jw> may lose data. The script contains information on recovery. > > jw> > > jw> http://people.freebsd.org/~jwd/memzil.txt > > jw> > > jw> Comments/Improvements appreciated. > > > > Why is simply setting sync=disabled to the ZFS dataset not enough? > > As you refer to, my understanding is that sync=disabled is at the dataset > layer. The zil approach is at the zpool layer - sync=disabled would be > nice at the zpool layer. Set it on the root dataset (meaning the dataset with the same name as the pool) and every child dataset will pick it up via inheritance.