From mboxrd@z Thu Jan 1 00:00:00 1970 From: Justin Piszcz Subject: Re: which raid level gives maximum overall speed? (raid-10,f2 vs. raid-0) Date: Tue, 5 Feb 2008 17:58:56 -0500 (EST) Message-ID: References: <20080130192133.17b254bf@szpak> <20080130220007.GG20173@rap.rap.dk> <20080130233639.5d46b044@szpak> <20080131015506.GB6617@rap.rap.dk> <20080205161036.GA30326@rap.rap.dk> <20080205200423.GB17621@rap.rap.dk> <20080205225534.GA32053@rap.rap.dk> Mime-Version: 1.0 Content-Type: MULTIPART/MIXED; BOUNDARY="-1463747160-1565307494-1202252336=:15698" Return-path: In-Reply-To: <20080205225534.GA32053@rap.rap.dk> Sender: linux-raid-owner@vger.kernel.org To: =?ISO-8859-15?Q?Keld_J=F8rn_Simonsen?= Cc: Janek Kozicki , linux-raid@vger.kernel.org List-Id: linux-raid.ids This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. ---1463747160-1565307494-1202252336=:15698 Content-Type: TEXT/PLAIN; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE On Tue, 5 Feb 2008, Keld J=F8rn Simonsen wrote: > On Tue, Feb 05, 2008 at 05:28:27PM -0500, Justin Piszcz wrote: >> >> >>> Could you give some figures? >> >> I remember testing with bonnie++ and raid10 was about half the speed >> (200-265 MiB/s) as RAID5 (400-420 MiB/s) for sequential output, but inpu= t >> was closer to RAID5 speeds/did not seem affected (~550MiB/s). > > Impressive. What levet of raid10 was involved? and what type of Like I said, it was baseline testing, so pretty much the default raid10=20 when you create it via mdadm, I did not mess with offsets, etc. > equipment, how many disks? Ten 10,000rpm raptors. > Maybe the better output for raid5 could be > due to some striping - AFAIK raid5 will be striping quite well, and > writes almost equal to reading time indicates that the writes are > striping too. > > best regards > keld > ---1463747160-1565307494-1202252336=:15698--