From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Smith Subject: paralellism of device use in md Date: Tue, 17 Jan 2006 12:09:27 +0000 Message-ID: <20060117120927.GU7017@strugglers.net> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="qqF1XwZUdAkx0x+N" Return-path: Content-Disposition: inline Sender: linux-raid-owner@vger.kernel.org To: linux-raid List-Id: linux-raid.ids --qqF1XwZUdAkx0x+N Content-Type: text/plain; charset=us-ascii Content-Disposition: inline I'm wondering: how well does md currently make use of the fact there are multiple devices in the different (non-parity) RAID levels for optimising reading and writing? For example, are *writes* to a 2 device RAID-0 approaching twice as fast as to a single device? If not, are they any faster at all? Are reads from a 2 device RAID-1 twice as fast as from a single device? If there are benefits, how quickly do they degrade to nothing as disks are added? What does the picture look like for reads and writes to a 4 device RAID-10? Sorry if my subject line isn't clear, but I coudn't think of a better way to put it. Thanks, Andy --qqF1XwZUdAkx0x+N Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.1 (GNU/Linux) iD8DBQFDzN53IJm2TL8VSQsRAgCPAKCW9f1SDORnLp9cmYlojntAgoiZTgCgiMq3 mEYPzLcdIqV1hVZxpQWJURU= =Kxuf -----END PGP SIGNATURE----- --qqF1XwZUdAkx0x+N--