From owner-freebsd-hackers@FreeBSD.ORG Wed Jan 23 21:49:38 2013 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id 074AB93B; Wed, 23 Jan 2013 21:49:38 +0000 (UTC) (envelope-from artemb@gmail.com) Received: from mail-vb0-f47.google.com (mail-vb0-f47.google.com [209.85.212.47]) by mx1.freebsd.org (Postfix) with ESMTP id AB8B6204; Wed, 23 Jan 2013 21:49:37 +0000 (UTC) Received: by mail-vb0-f47.google.com with SMTP id e21so1664343vbm.6 for ; Wed, 23 Jan 2013 13:49:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:x-received:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type; bh=z4/E1kLIId/DXawG3IwyNiUPD7HpgHwVXChoKr62Ehs=; b=otq09/+ZHVb0J5x6vQY6LCtcvyBozJEi7CUmJ9PybWB0PbtqGiYL5Ji9lr+JL9I0Gd NIfIuY17oqebpp93lkjUM0p+nUce+/f18QkKfSus6DExRPptLDWvfcXox/PC5Dsz68Z5 iQ4vHz14I4l8wOHMvyFFpG/K1TL4zh3U6KhGLDJjcVGv1yvq/mWCEgAAFL4SIe+z/tPx nD2EUdxovoIp/PsHJC5Wa4HLw9/+miFcQqOk4waDE7c/BjX6g6T4QXb7NRmIV8Z4H2ki /3/kd6qL5Nujb0G/4y9EYSyFC8wehQ4IjZGf4mqujActecSvqEOGRxwKuon+1nfvKl0o 8fhw== MIME-Version: 1.0 X-Received: by 10.220.156.197 with SMTP id y5mr3146793vcw.17.1358977777180; Wed, 23 Jan 2013 13:49:37 -0800 (PST) Sender: artemb@gmail.com Received: by 10.220.123.2 with HTTP; Wed, 23 Jan 2013 13:49:37 -0800 (PST) In-Reply-To: References: <20130122073641.GH30633@server.rulingia.com> Date: Wed, 23 Jan 2013 13:49:37 -0800 X-Google-Sender-Auth: vIBQ5fJ98BDdbeD0elQH_y-D0JM Message-ID: Subject: Re: ZFS regimen: scrub, scrub, scrub and scrub again. From: Artem Belevich To: Wojciech Puchar Content-Type: text/plain; charset=ISO-8859-1 Cc: freebsd-fs , FreeBSD Hackers X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 23 Jan 2013 21:49:38 -0000 On Wed, Jan 23, 2013 at 1:25 PM, Wojciech Puchar wrote: >>> gives single drive random I/O performance. >> >> >> For reads - true. For writes it's probably behaves better than RAID5 > > > yes, because as with reads it gives single drive performance. small writes > on RAID5 gives lower than single disk performance. > > >> If you need higher performance, build your pool out of multiple RAID-Z >> vdevs. > > even you need normal performance use gmirror and UFS I've no objection. If it works for you -- go for it. For me personally ZFS performance is good enough, and data integrity verification is something that I'm willing to sacrifice some performance for. ZFS scrub gives me either warm and fuzzy feeling that everything is OK, or explicitly tells me that something bad happened *and* reconstructs the data if it's possible. Just my $0.02, --Artem