From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Snook Subject: Re: Performance Characteristics of All Linux RAIDs (mdadm/bonnie++) Date: Wed, 28 May 2008 12:40:00 -0400 Message-ID: <483D8AE0.8090606@redhat.com> References: <95711f160805280934y77ed7d91tec5aeb531bf8013c@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <95711f160805280934y77ed7d91tec5aeb531bf8013c@mail.gmail.com> Sender: linux-raid-owner@vger.kernel.org To: =?ISO-8859-1?Q?Jens_B=E4ckman?= Cc: Justin Piszcz , linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, xfs@oss.sgi.com List-Id: linux-raid.ids Jens B=E4ckman wrote: > On Wed, May 28, 2008 at 10:53 AM, Justin Piszcz wrote: >> Results: >> >> http://home.comcast.net/~jpiszcz/raid/20080528/raid-levels.html >> http://home.comcast.net/~jpiszcz/raid/20080528/raid-levels.txt >=20 > Either the RAID 1 read speed must be wrong, or something is odd in th= e > Linux implementation. There's six drives that can be used for reading > at the same time, as they contain the very same data. 63MB/s > sequential looks like what you would get from a single drive. The test is a single thread reading one block at a time, so this is not= =20 surprising. If you get this doing multi-megabyte readahead, or with=20 several threads, something is very wrong. -- Chris -- To unsubscribe from this list: send the line "unsubscribe linux-raid" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html