From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lists.gentoo.org ([140.105.134.102] helo=robin.gentoo.org) by nuthatch.gentoo.org with esmtp (Exim 4.43) id 1Dqx7w-0007VB-Ni for garchives@archives.gentoo.org; Fri, 08 Jul 2005 17:59:05 +0000 Received: from robin.gentoo.org (localhost [127.0.0.1]) by robin.gentoo.org (8.13.4/8.13.4) with SMTP id j68Hvh9w009606; Fri, 8 Jul 2005 17:57:43 GMT Received: from perch.kroah.org (mail.kroah.org [69.55.234.183]) by robin.gentoo.org (8.13.4/8.13.4) with ESMTP id j68Hrqx9018254 for ; Fri, 8 Jul 2005 17:53:52 GMT Received: from [192.168.0.10] (c-24-22-115-24.hsd1.or.comcast.net [24.22.115.24]) (authenticated) by perch.kroah.org (8.11.6/8.11.6) with ESMTP id j68HrZq12371 for ; Fri, 8 Jul 2005 10:53:35 -0700 Received: from greg by echidna.kroah.org with local (masqmail 0.2.19) id 1DqwPE-80y-00 for ; Fri, 08 Jul 2005 10:12:52 -0700 Date: Fri, 8 Jul 2005 10:12:52 -0700 From: Greg KH To: gentoo-dev@lists.gentoo.org Subject: Re: [gentoo-dev] devfs is dead, let's move on Message-ID: <20050708171252.GD29606@kroah.com> References: <20050706224651.GA19853@kroah.com> <1120745893.11567.42.camel@cgianelloni.nuvox.net> Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-dev@gentoo.org Reply-to: gentoo-dev@lists.gentoo.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1120745893.11567.42.camel@cgianelloni.nuvox.net> User-Agent: Mutt/1.5.8i X-Archives-Salt: 37087b8e-14c8-46fd-8c4c-e64dc4857729 X-Archives-Hash: 956e67fb8c2272ffe13ab60fceaad24c On Thu, Jul 07, 2005 at 10:18:12AM -0400, Chris Gianelloni wrote: > On Wed, 2005-07-06 at 15:46 -0700, Greg KH wrote: > > To start with, the 061 version of udev offers a big memory savings if > > you use the "default" kernel name of a device[3]. If you do that, it does > > not create a file in its database in /dev/.udevdb/ > > So if we were to switch to udev 061 in genkernel, it would shrink memory > usage in our initrd/initramfs, provided we made everything use the LSB > device names/nodes, versus the devfs ones, correct? Not in the initrd/initramfs, but in the tmpfs partition that udev uses to create the /dev entries. Well, I guess you could say the "initrd/initramfs" if that is where udev is mounted on early startup (I haven't looked at how genkernel does this in a long time, sorry.) And yes, the memory savings is there, if we use the LSB names only vs the devfs name and the symlink like we currently do. To see this, look at how much space /dev/.udevdb/ takes up right now with 062 udev. Then change the following rules in /etc/udev/rules.d/50-udev.rules with the diff at the end of this email. Then reboot and look at the size of the /dev/.udevdb/ directory again. I think you will notice a huge space savings. thanks, greg k-h --- 50-udev.rules.orig 2005-07-08 10:10:24.000000000 -0700 +++ 50-udev.rules 2005-07-08 10:11:16.000000000 -0700 @@ -139,9 +139,9 @@ # tty devices KERNEL=="console", NAME="%k", GROUP="tty", MODE="0600" KERNEL=="tty", NAME="%k", GROUP="tty", MODE="0666" -KERNEL=="tty[0-9]*", NAME="vc/%n", SYMLINK+="%k", GROUP="tty" -KERNEL=="ttyS[0-9]*", NAME="tts/%n", SYMLINK+="%k", GROUP="tty" -KERNEL=="ttyUSB[0-9]*", NAME="tts/USB%n", GROUP="tty", MODE="0660" +KERNEL=="tty[0-9]*", NAME="%k", GROUP="tty" +KERNEL=="ttyS[0-9]*", NAME="%k", GROUP="tty" +KERNEL=="ttyUSB[0-9]*", NAME="%k", GROUP="tty", MODE="0660" KERNEL=="ippp0", NAME="%k", GROUP="tty" KERNEL=="isdn*" NAME="%k", GROUP="tty" KERNEL=="dcbri*", NAME="%k", GROUP="tty" @@ -149,14 +149,14 @@ # pty devices KERNEL=="ptmx", NAME="%k", GROUP="tty", MODE="0666" -KERNEL=="pty[p-za-e][0-9a-f]*", NAME="pty/m%n", SYMLINK+="%k", GROUP="tty" -KERNEL=="tty[p-za-e][0-9a-f]*", NAME="pty/s%n", SYMLINK+="%k", GROUP="tty" +KERNEL=="pty[p-za-e][0-9a-f]*", NAME="%k", GROUP="tty" +KERNEL=="tty[p-za-e][0-9a-f]*", NAME="%k", GROUP="tty" # vc devices -KERNEL=="vcs", NAME="vcc/0", SYMLINK+="%k", GROUP="tty" -KERNEL=="vcs[0-9]*", NAME="vcc/%n", SYMLINK+="%k", GROUP="tty" -KERNEL=="vcsa", NAME="vcc/a0", SYMLINK+="%k", GROUP="tty" -KERNEL=="vcsa[0-9]*", NAME="vcc/a%n", SYMLINK+="%k", GROUP="tty" +KERNEL=="vcs", NAME="%k", GROUP="tty" +KERNEL=="vcs[0-9]*", NAME="%k", GROUP="tty" +KERNEL=="vcsa", NAME="%k", GROUP="tty" +KERNEL=="vcsa[0-9]*", NAME="%k", GROUP="tty" # memory devices KERNEL=="random", NAME="%k", MODE="0666" -- gentoo-dev@gentoo.org mailing list