From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roberto Spadim Subject: Re: md road-map: 2011 Date: Wed, 16 Feb 2011 23:30:43 -0200 Message-ID: References: <20110216212751.51a294aa@notabene.brown> <4D5BB4EA.8030907@texsoft.it> <20110216140024.GA18707@cthulhu.home.robinhill.me.uk> <20110217085505.1deec298@notabene.brown> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20110217085505.1deec298@notabene.brown> Sender: linux-raid-owner@vger.kernel.org To: NeilBrown Cc: Giovanni Tessore , linux-raid@vger.kernel.org List-Id: linux-raid.ids =3D] i agree with you on all cases :) the idea of a generic raid10 for raid1,0,10 isn't good for low cpu/ram (in other words increase performace) know i understand why raid10 raid1 raid0 are diferent files and raid456= only one let=B4s try the option2: could we implement layout/offset to raid1? it=B4s a read performace improvement (maybe write problem) for example, odd sectors on start of disk1 and end of disk2, even sectors on end of disk1 and start of disk2 or another layouts like raid10 2011/2/16 NeilBrown : > On Wed, 16 Feb 2011 11:21:50 -0300 Roberto Spadim > wrote: > >> since we have the option1 done, why continue with raid1 code? could = we >> port write-behind to raid10 code? > > No. =A0write-behind depends on write-mostly, and write-mostly only re= ally makes > sense for RAID1. =A0I much prefer to keep these two code bases separa= te. > >> another thing, could raid10 work without replica? like a raid0? > > Why don't you try it? =A0Choose a layout that asks for only 1 copy of= the data. > It should work. > >> >> why? just to remove many files with the same function (raid1and raid= 0, >> if raid10 do the same work, many some mdadm changes allow us to >> --level=3D1 to understand that's raid10 without stripe, --level=3D0 = is >> raid10 without mirrors) > > Again, RAID0 has some features that RAID10 doesn'tand cannot. =A0I su= ggest you > read man pages (e.g. 'man md') to find out the details. > > Also the RAID0 code is much simpler and hence possibly faster. > > NeilBrown > > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid"= in > the body of a message to majordomo@vger.kernel.org > More majordomo info at =A0http://vger.kernel.org/majordomo-info.html > --=20 Roberto Spadim Spadim Technology / SPAEmpresarial -- 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