From mboxrd@z Thu Jan 1 00:00:00 1970 From: Volker Armin Hemmann Subject: Re: Linux mdadm superblock question. Date: Wed, 17 Feb 2010 19:46:08 +0100 Message-ID: <201002171946.09884.volkerarmin@googlemail.com> References: <201002140251.59668.volkerarmin@googlemail.com> <201002171927.07051.volkerarmin@googlemail.com> <20100217183703.GA15446@emergent.ellipticsemi.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20100217183703.GA15446@emergent.ellipticsemi.com> Sender: linux-kernel-owner@vger.kernel.org To: Nick Bowler Cc: david@lang.hm, Kyle Moffett , Rudy Zijlstra , Neil Brown , "Mr. James W. Laferriere" , Bill Davidsen , Michael Evans , linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org List-Id: linux-raid.ids On Mittwoch 17 Februar 2010, Nick Bowler wrote: > On 19:27 Wed 17 Feb , Volker Armin Hemmann wrote: > > On Mittwoch 17 Februar 2010, Nick Bowler wrote: > > > On 09:41 Wed 17 Feb , david@lang.hm wrote: > > > > for a distro that is trying to make one kernel image run on eve= ry > > > > possible type of hardware features like initramfs (and udev, > > > > modeules, etc) are wonderful. > > > >=20 > > > > however for people who run systems that are known ahead of time= and > > > > static (and who build their own kernels instead of just relying= on > > > > the distro default kernel), all of this is unnessesary complica= tion, > > > > which leaves more room for problems to creep in. > > >=20 > > > Such people can easily construct an initramfs containing busybox = and > > > mdadm with a shell script hardcoded to mount their root fs and ru= n > > > switch_root. It's a ~10 minute jobbie that only needs to be done= once. > >=20 > > and even better when you don't have to do that one time job at all. >=20 > But people who are building their own kernels are already doing a > (much harder, imo) one time job of configuring their kernels. >=20 > > btw, what about additional delay? >=20 > It takes about half a second for mdadm to assemble my root array, is > that what you're referring to? >=20 > I assume that kernel auto-assembly is no faster, although I've never > used it. Regardless, half a second isn't very long to wait. well at the moment it takes less than two seconds until init takes over= =2E Adding .5 seconds is a lot. And loading the initrd and changing root is= n't=20 free either, true? I remember well all the noise in the past about making linux booting fa= ster.=20 So why slow it down with an initrd - especially if you can do without? Gl=FCck Auf, Volker