From owner-freebsd-fs@FreeBSD.ORG Fri Sep 24 21:12:07 2010 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 2438F106564A for ; Fri, 24 Sep 2010 21:12:07 +0000 (UTC) (envelope-from peterjeremy@acm.org) Received: from mail15.syd.optusnet.com.au (mail15.syd.optusnet.com.au [211.29.132.196]) by mx1.freebsd.org (Postfix) with ESMTP id A769E8FC14 for ; Fri, 24 Sep 2010 21:12:06 +0000 (UTC) Received: from server.vk2pj.dyndns.org (c220-239-116-103.belrs4.nsw.optusnet.com.au [220.239.116.103]) by mail15.syd.optusnet.com.au (8.13.1/8.13.1) with ESMTP id o8OLC3dK028281 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sat, 25 Sep 2010 07:12:04 +1000 X-Bogosity: Ham, spamicity=0.000000 Received: from server.vk2pj.dyndns.org (localhost.vk2pj.dyndns.org [127.0.0.1]) by server.vk2pj.dyndns.org (8.14.4/8.14.4) with ESMTP id o8OLC1FU021848; Sat, 25 Sep 2010 07:12:01 +1000 (EST) (envelope-from peter@server.vk2pj.dyndns.org) Received: (from peter@localhost) by server.vk2pj.dyndns.org (8.14.4/8.14.4/Submit) id o8OLC0QD021847; Sat, 25 Sep 2010 07:12:00 +1000 (EST) (envelope-from peter) Date: Sat, 25 Sep 2010 07:12:00 +1000 From: Peter Jeremy To: Zaphod Beeblebrox Message-ID: <20100924211200.GA49476@server.vk2pj.dyndns.org> References: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="PNTmBPCT7hxwcZjr" Content-Disposition: inline In-Reply-To: X-PGP-Key: http://members.optusnet.com.au/peterjeremy/pubkey.asc User-Agent: Mutt/1.5.20 (2009-06-14) Cc: freebsd-fs Subject: Re: Oracle to deny deduplication? X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 24 Sep 2010 21:12:07 -0000 --PNTmBPCT7hxwcZjr Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 2010-Sep-22 00:26:20 -0400, Zaphod Beeblebrox wrote: >On Tue, Sep 21, 2010 at 3:21 PM, Bob Friesenhahn > wrote: >> On Tue, 21 Sep 2010, Zaphod Beeblebrox wrote: >>> >>> Shortly thereafter I found a nice table (here: >>> http://docs.sun.com/app/docs/doc/819-5461/appendixa-1?a=3Dview ) >>> >>> ... now notice that the official Oracle table lists version 21 of >>> zpool as "Reserved" ... this worries me. =A0Is the solution to the >>> lawsuit against Sun by NetApp (that Oracle settled) that Oracle burys >>> deduplication? =A0This could be bad for people who unbury it. > >Even if you are correct, I'm still quite wary of Oracle's support of >ZFS. Oracle is not known as a "nice" entity. Agreed, but in this case, I also suspect that it's more of a technical issue than a legal issue. >But how would that work --- if you update the pool to 23 (22 or 23 is >the latest listed there?) then a filesystem with dedup would be read >... but you might not be able to set the attribute? Seems odd. It depends exactly what Oracle have done to the code. About the only way to get a definitive answer would be to create a v22 or v23 pool with dedup enabled and then attempt to import the pool on a S10U9 system. > The >ZFS implementation of dedup seems so "sensible" ... Maybe, but if you read some of the ZFS lists, you'll quickly find that lots of people ran into problems with it. Probably the biggest issue is the massive amount of cache you need with it (either RAM or a really fast L2ARC) - quite a few people got burnt creating dedup- enabled pools with snapshots that they then couldn't destroy in a realistic time. And my feeling was that there seemed to be a higher- than-usual level of other issues that people were reporting with dedup. As a SOHO user, I don't believe I'll be able to justify the cache costs associated with dedup, though I can see the benefits in some environments. Hopefully, the problems will be able to resolved and dedup will be "officially" available at some point in the future. --=20 Peter Jeremy --PNTmBPCT7hxwcZjr Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.15 (FreeBSD) iEYEARECAAYFAkydFCAACgkQ/opHv/APuIeqowCfeENwvWQWMefOVhA3LA+XiiUP 8PMAn2PW+VakkNVv2Y0VgyadoljKDCF/ =msUp -----END PGP SIGNATURE----- --PNTmBPCT7hxwcZjr--