Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932791Ab2K3LZA (ORCPT ); Fri, 30 Nov 2012 06:25:00 -0500 Received: from mga01.intel.com ([192.55.52.88]:38331 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755996Ab2K3LY7 (ORCPT ); Fri, 30 Nov 2012 06:24:59 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.84,191,1355126400"; d="asc'?scan'208";a="257106923" Message-ID: <1354274749.30168.100.camel@sauron.fi.intel.com> Subject: Re: [RFC/PATCH 0/1] ubi: Add ubiblock driver From: Artem Bityutskiy Reply-To: dedekind1@gmail.com To: Thomas Petazzoni Cc: Ezequiel Garcia , Linux Kernel Mailing List , linux-mtd@lists.infradead.org, David Woodhouse , Tim Bird , Michael Opdenacker Date: Fri, 30 Nov 2012 13:25:49 +0200 In-Reply-To: <20121121110022.35db364f@skate> References: <20121121110022.35db364f@skate> Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-i2CwBWG4xzGI4IyrUVcu" X-Mailer: Evolution 3.4.4 (3.4.4-2.fc17) Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2366 Lines: 63 --=-i2CwBWG4xzGI4IyrUVcu Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Wed, 2012-11-21 at 11:00 +0100, Thomas Petazzoni wrote: > While I think the original ubiblk that was read-only made sense to > allow the usage of read-only filesystems like squashfs, I am not sure > a > read/write ubiblock is useful. >=20 > Using a standard block read/write filesystem on top of ubiblock is > going > to cause damage to your flash. Even though UBI does wear-leveling, > your > standard block read/write filesystem will think it has 512 bytes block > below him, and will do a crazy number of writes to small blocks. Even > though you have a one LEB cache, it is going to be defeated quite > strongly by the small random I/O of the read/write filesystem. Well, in practice normal file-system do 4K-aligned I/O, without crazy things, and try to do I/O sequentially. >=20 > I am not sure letting people use read/write block filesystems on top > of > flashes, even through UBI, is a good idea.=20 Why not? --=20 Best Regards, Artem Bityutskiy --=-i2CwBWG4xzGI4IyrUVcu Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAABAgAGBQJQuJe9AAoJECmIfjd9wqK0JH8QAMEXkfGsP2PYdfTSjhJWedZw PbHELNoFTjFwlGzRCV3ulDzx/QnQXiyIS80ZZWQO68KCTNhCrryCouJRp6uWANYR jzZboy8hCkK9I7kbLtLEbPHXhzM7awAIhKMAsh1d4k5L5/ywIZUouyhYXO+01gLj MNszGGTQllTDGwpaqLJLcKmo7RL1GjOUUspiKkzjIc0zIwD64ThPTxa4hcCYzU+2 3xnDk6x9BlInw1E9FV/tFVnVDUXTomYMMFOkkjnr7gaXJees7TAUp5U/7Mf7REQA oR0+BX55LBKAx8h+MCORA98FFeIR45qYTIXnEBEZ5kCPJt4v33YMtyu7FzbjRhpm PdLhSwwGnNWlumVuKLeu9stb9nxNoOoAZ1XzJJKxUHqbFMn/MakmYHilQv6ZWsP7 kU8vcrXpEvhcg95vH+MW4T8mYIY4+7luZ7oOItOrW7bINVUNPBXDm6jXx8ublZRP ovcxUN1JbT+lsoDqqf0fX5/d49Kd+cn/taGFAhDCwQ0Fe4A2iV+fzEPlctkF4JSn yKsVizY4xhVRArNVJTIZpeSbkFP53sXYuNcJxhqHLRj3flkRUSuDIT3bM2Z6fd6O 5zETVWw7VdyqSHwNtMYfNB2Ya6Ma8y5dP2qi0+W2TqovW4Ioxtv2/Pu7Zq/DH/Kv jDgaW6Da62lPbi7wCtfs =OlJK -----END PGP SIGNATURE----- --=-i2CwBWG4xzGI4IyrUVcu-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/