From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Brian J. Murrell" Subject: Re: dmraid - where is the raid done? Date: Tue, 28 Oct 2008 07:49:07 -0400 Message-ID: <1225194547.16984.69.camel@pc.ilinx> References: <1225120062.20830.34.camel@pc.ilinx> <49064EF0.4080804@gmail.com> <1225154175.16984.16.camel@pc.ilinx> <490666F0.4000306@gmail.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-51xNllKqnwuu7PSzZsBf" Return-path: In-Reply-To: <490666F0.4000306@gmail.com> Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids --=-51xNllKqnwuu7PSzZsBf Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Mon, 2008-10-27 at 20:12 -0500, Roger Heflin wrote: >=20 > If it is an out-of-kernel driver, then the work is being done in the=20 > manufacturer's driver. I see. > If it is dmraid it is being done in the dmraid driver. Ahhh. So in the above "out of kernel driver" instance that is a case where dmraid is not handling it, yes? > If there is no underlying hardware to run the raid on then everything has > to be done in the OS. Indeed. I had just wondered if these "fakeraid" solutions where at least fanning out the copy (in the case of mirror) themselves, saving the doubling of PCI bus traffic. > All of the real raid cards have at least a > really basic microprocesser on the card that takes care of things. Yeah, I'm fairly familiar with the concepts of real RAID hardware. It was this new fakeraid I was wondering about. Thanx for the enlightenment though. The one last value that I had hope for in the fakeraid arena seems to be invalid so I have to start to agree with the documentation I've read and really have to wonder the value of the fakeraid, especially and until the on-disk formats are standardized. Not being able to move fakeraid disks from one manufacturer to another is a real impediment in my mind. b. --=-51xNllKqnwuu7PSzZsBf Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEABECAAYFAkkG/DMACgkQl3EQlGLyuXAT1gCfUWe13xLh7t4jrBh7XLstb/fl SLAAoJ0orejGvD52UCOLh1EoiE59IO8O =BQzx -----END PGP SIGNATURE----- --=-51xNllKqnwuu7PSzZsBf--