From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) by finch.gentoo.org (Postfix) with ESMTP id 7281B138010 for ; Sun, 26 Aug 2012 02:07:14 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 0E5ABE059C; Sun, 26 Aug 2012 02:06:46 +0000 (UTC) Received: from mailout-de.gmx.net (mailout-de.gmx.net [213.165.64.22]) by pigeon.gentoo.org (Postfix) with SMTP id 0AA8DE04EB for ; Sun, 26 Aug 2012 02:04:33 +0000 (UTC) Received: (qmail invoked by alias); 26 Aug 2012 02:04:33 -0000 Received: from wl-l3-55.rz.tu-ilmenau.de (EHLO localhost) [141.24.17.55] by mail.gmx.net (mp072) with SMTP; 26 Aug 2012 04:04:33 +0200 X-Authenticated: #4040096 X-Provags-ID: V01U2FsdGVkX1+v6KdahJqvqP0RflQsITY02JmD/wIHQdPEgq7CTG 0L5nN7LdmKtOIt Date: Sun, 26 Aug 2012 04:04:32 +0200 From: Frank Steinmetzger To: gentoo-user@lists.gentoo.org Subject: Re: [gentoo-user] SSD performance tweaking Message-ID: <20120826020432.GB5995@eisen.lan> Mail-Followup-To: gentoo-user@lists.gentoo.org References: <503602B8.3050507@wonkology.org> <20120824092548.GA13922@eisen.lan> <64095489.fUK2STuJpF@energy> Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="vGgW1X5XWziG23Ko" Content-Disposition: inline In-Reply-To: <64095489.fUK2STuJpF@energy> User-Agent: Mutt 1.5.21 (2010-09-15, Gentoo 1.5.21-r10) X-Y-GMX-Trusted: 0 X-Archives-Salt: bbf898eb-fdfa-4dcb-be33-0edc14822f1c X-Archives-Hash: 5855c905296652fd3c940048ec543023 --vGgW1X5XWziG23Ko Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sun, Aug 26, 2012 at 12:22:47AM +0200, Volker Armin Hemmann wrote: > > > The size of an erasable block of SSDs is even larger, usually 512K, it > > > would be best to align to that, too. A partition offset of 512K or 1M > > > would avoid this. > >=20 > > Unless the filesystem knows this and starts bigger files at those 512 k > > boundaries (so really only one erase cycle is needed for files <=3D512 = k), > > isn't this fairly superfluous? >=20 > no, if you misalign, a lot of 4k blocks might span into two erase blocks.= =20 > Which is bad. If you align correctly, you will never cross them unnecess= ary,=20 > sparing your SSD some unnecessary writes and improving overall performanc= e.=20 I don=E2=80=99t quite follow. If you align to 4k, then you are also aligne= d to 512k, because 512 % 4 =3D 0. --=20 Gru=C3=9F | Greetings | Qapla' Please do not share anything from, with or about me with any Facebook servi= ce. The duration of a minute is relative. It depends on the side of the toilet door you are standing on. --vGgW1X5XWziG23Ko Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (GNU/Linux) iEYEARECAAYFAlA5hDAACgkQGafpl66MV0zR9gCgj33cRyAUGKlGeqxw69VHv4up MCoAnRvlLYsv/IQGQnLAIGPt0+RemzJo =jASx -----END PGP SIGNATURE----- --vGgW1X5XWziG23Ko--