From owner-freebsd-fs@FreeBSD.ORG Tue Jun 21 03:16:02 2011 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 D5C1A1065675 for ; Tue, 21 Jun 2011 03:16:02 +0000 (UTC) (envelope-from james@jlauser.net) Received: from mail-gx0-f182.google.com (mail-gx0-f182.google.com [209.85.161.182]) by mx1.freebsd.org (Postfix) with ESMTP id 8BAF38FC14 for ; Tue, 21 Jun 2011 03:16:02 +0000 (UTC) Received: by gxk28 with SMTP id 28so2385773gxk.13 for ; Mon, 20 Jun 2011 20:16:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=jlauser.net; s=google; h=domainkey-signature:mime-version:date:message-id:subject:from:to :content-type; bh=wW3fUh9Dzt+F9W6xGDwrTtD+sCxLvwkkcxcQLwXBOww=; b=l0F0n8Eo0BuD7zEnd7ODqXKtGOL/09/sk1gLQyEeR/IisO5WT3+zxYKWYaD997tM+s 6GrabgOSnNUieBOs/LmbzPxdU6WtyhARUb4fPnWP+SElm1h96Jrf6F2+C/gZRkepEIuh WI898eaHoain41xiiqVzcK65xZV+lDDZXFhxI= DomainKey-Signature: a=rsa-sha1; c=nofws; d=jlauser.net; s=google; h=mime-version:date:message-id:subject:from:to:content-type; b=T8Z4DbesigXPra7lUPsP2pz/FhsPl63qUx+3ps1CKSvmI+rNEkt6PsWy4nmVuHKWdw B+U4IWJE1nj/+PHTNp82gpxkxTE3vrXxHUNbFJ/RfgIgqfdZNd1EHtahAOxbzjqQF5iS a6jbOuixnhjaneh4Os4AA1vqBCMrXbxSbbDCg= Received: by 10.91.201.4 with SMTP id d4mr6731400agq.41.1308624373056; Mon, 20 Jun 2011 19:46:13 -0700 (PDT) Received: from mail-gw0-f54.google.com (mail-gw0-f54.google.com [74.125.83.54]) by mx.google.com with ESMTPS id c63sm401399yhe.18.2011.06.20.19.46.11 (version=TLSv1/SSLv3 cipher=OTHER); Mon, 20 Jun 2011 19:46:12 -0700 (PDT) Received: by gwb15 with SMTP id 15so1248195gwb.13 for ; Mon, 20 Jun 2011 19:46:11 -0700 (PDT) MIME-Version: 1.0 Received: by 10.236.32.67 with SMTP id n43mr3209959yha.161.1308624371390; Mon, 20 Jun 2011 19:46:11 -0700 (PDT) Received: by 10.236.202.234 with HTTP; Mon, 20 Jun 2011 19:46:11 -0700 (PDT) Date: Mon, 20 Jun 2011 22:46:11 -0400 Message-ID: From: "James L. Lauser" To: freebsd-fs@freebsd.org Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Subject: ZFSv28 Dedup question 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: Tue, 21 Jun 2011 03:16:02 -0000 I have a (hopefully) simple question about ZFSv28 deduplication that is not very clearly answered in any of the documentation I've found. If I enable dedupe on a dataset, will newly written data dedupe against old data that was written before dedupe was enabled? If not, is it worth forcing the data to be rewritten so that it makes it into the appropriate tables? -- James L. Lauser james@jlauser.net http://jlauser.net/