From owner-freebsd-stable@FreeBSD.ORG Wed Feb 8 18:40:46 2012 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 5B1891065672 for ; Wed, 8 Feb 2012 18:40:46 +0000 (UTC) (envelope-from fjwcash@gmail.com) Received: from mail-vx0-f182.google.com (mail-vx0-f182.google.com [209.85.220.182]) by mx1.freebsd.org (Postfix) with ESMTP id 1337F8FC14 for ; Wed, 8 Feb 2012 18:40:45 +0000 (UTC) Received: by vcmm1 with SMTP id m1so817441vcm.13 for ; Wed, 08 Feb 2012 10:40:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; bh=abZF8ULYPDB3Sg1emaka80UjTj6DJiQaAft9o5r4reg=; b=cEe5CFnP5N6g8kY6J4+abUpbOxa03RtMmxvuNDL4zb4IK8lktOoFCmbCFxAMbRU4Ep GJN5SI5+0yD0GNCKsnza8a7JYu3dUag9MZ3o8qVi6Ni6N2bdQMZXeZju8Jc5+2pL1kCq 01snZq8dTm44UAKTmhTG89Y+3nxw7RbsVPB4M= MIME-Version: 1.0 Received: by 10.52.33.239 with SMTP id u15mr12713684vdi.49.1328726445282; Wed, 08 Feb 2012 10:40:45 -0800 (PST) Received: by 10.220.181.4 with HTTP; Wed, 8 Feb 2012 10:40:45 -0800 (PST) In-Reply-To: References: <4F30E284.8080905@norma.perm.ru> <4F310115.3070507@FreeBSD.org> <4F310C5A.6070400@norma.perm.ru> <4F310E75.7090301@FreeBSD.org> <4F3144A9.2000505@norma.perm.ru> <4F314892.50806@FreeBSD.org> <4F314B5B.100@norma.perm.ru> <4F3186C6.8000904@FreeBSD.org> <4F324F10.2060508@norma.perm.ru> <20120208131537.00004c01@unknown> <4F32BE0B.7000703@norma.perm.ru> Date: Wed, 8 Feb 2012 10:40:45 -0800 Message-ID: From: Freddie Cash To: "Eugene M. Zheganin" Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Cc: freebsd-stable Subject: Re: zfs arc and amount of wired memory X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 08 Feb 2012 18:40:46 -0000 On Wed, Feb 8, 2012 at 10:40 AM, Freddie Cash wrote: > On Wed, Feb 8, 2012 at 10:25 AM, Eugene M. Zheganin w= rote: >> On 08.02.2012 18:15, Alexander Leidinger wrote: >>> I can't remember to have seen any mention of SWAP on ZFS being safe >>> now. So if nobody can provide a reference to a place which tells that >>> the problems with SWAP on ZFS are fixed: >>> =C2=A01. do not use SWAP on ZFS >>> =C2=A02. see 1. >>> =C2=A03. check if you see the same problem without SWAP on ZFS (btw. se= e 1.) >>> >> So, if a swap have to be used, and, it has to be backed up with somethin= g >> like gmirror so it won't come down with one of the disks, there's no nee= d to >> use zfs for system. >> >> This makes zfs only useful in cases where you need to store something on= a >> couple+ of terabytes, still having OS on ufs. Occam's razor and so on. > > Or, you plug a USB stick into the back (or even inside the case as a > lot of mobos have internal USB connectors now) and use that for swap. That also works well for adding L2ARC (cache) to the ZFS pool as well. --=20 Freddie Cash fjwcash@gmail.com