From owner-freebsd-fs@FreeBSD.ORG  Fri Mar 22 15:26:59 2013
Return-Path: <owner-freebsd-fs@FreeBSD.ORG>
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 D46CDE59
 for <freebsd-fs@freebsd.org>; Fri, 22 Mar 2013 15:26:59 +0000 (UTC)
 (envelope-from zeus@ibs.dn.ua)
Received: from relay.ibs.dn.ua (relay.ibs.dn.ua [91.216.196.25])
 by mx1.freebsd.org (Postfix) with ESMTP id 5C26E6C4
 for <freebsd-fs@freebsd.org>; Fri, 22 Mar 2013 15:26:58 +0000 (UTC)
Received: from ibs.dn.ua (relay.ibs.dn.ua [91.216.196.25]) 
 by relay.ibs.dn.ua with ESMTP id r2MFQvEH095913
 for <freebsd-fs@freebsd.org>; Fri, 22 Mar 2013 17:26:57 +0200 (EET)
Message-ID: <20130322172657.95912@relay.ibs.dn.ua>
Date: Fri, 22 Mar 2013 17:26:57 +0300
From: Zeus Panchenko <zeus@ibs.dn.ua>
To: <freebsd-fs@freebsd.org>
cc: 
Subject: RAM amount recommendations for ZFS pools with ZIL and L2ARC on SSD
Organization: I.B.S. LLC
X-Mailer: MH-E 8.3.1; GNU Mailutils 2.99.97; GNU Emacs 24.0.93
X-Face: &sReWXo3Iwtqql1[My(t1Gkx;
 y?KF@KF`4X+'9Cs@PtK^y%}^.>Mtbpyz6U=,Op:KPOT.uG
 )Nvx`=er!l?WASh7KeaGhga"1[&yz$_7ir'cVp7o%CGbJ/V)j/=]vzvvcqcZkf; JDurQG6wTg+?/xA
 go`}1.Ze//K; Fk&/&OoHd'[b7iGt2UO>o(YskCT[_D)kh4!yY'<&:yt+zM=A`@`~9U+P[qS:f;
 #9z~ Or/Bo#N-'S'!'[3Wog'ADkyMqmGDvga?WW)qd=?)`Y&k=o}>!ST\
MIME-Version: 1.0
Content-Type: text/plain
Content-Transfer-Encoding: quoted-printable
X-BeenThere: freebsd-fs@freebsd.org
X-Mailman-Version: 2.1.14
Precedence: list
Reply-To: Zeus Panchenko <zeus@ibs.dn.ua>
List-Id: Filesystems <freebsd-fs.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/options/freebsd-fs>,
 <mailto:freebsd-fs-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-fs>
List-Post: <mailto:freebsd-fs@freebsd.org>
List-Help: <mailto:freebsd-fs-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-fs>,
 <mailto:freebsd-fs-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Fri, 22 Mar 2013 15:26:59 -0000

=2D----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

hi all,

while discovering the subj, I found recommendations at:
http://doc.freenas.org/index.php/Hardware_Recommendations#RAM

=2D ---------------------------------------------------------------------
... a general rule of thumb is 1 GB of RAM for every 1TB of storage ...
If you plan to use ZFS deduplication, a general rule of thumb is 5 GB
RAM per TB of storage to be deduplicated.
=2D ---------------------------------------------------------------------


so, are these recommendations correct for ZFS pools with ZIL and L2ARC
on SSD configurations?

are there corellations between "RAM amount" and "with/without ZIL, L2ARC
on separate devices pool configuration" ?

=2D --=20
Zeus V. Panchenko				jid:zeus@im.ibs.dn.ua
IT Dpt., I.B.S. LLC					  GMT+2 (EET)
=2D----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.19 (FreeBSD)

iEYEARECAAYFAlFMeEEACgkQr3jpPg/3oyr6awCfYllLOsUVicDA6OHt644HHQNF
aSUAn0lvTY86uKdm1D3nT6lz7KxmuRyA
=3D9DNs
=2D----END PGP SIGNATURE-----