Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757633AbZCBQaT (ORCPT ); Mon, 2 Mar 2009 11:30:19 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753691AbZCBQaD (ORCPT ); Mon, 2 Mar 2009 11:30:03 -0500 Received: from nf-out-0910.google.com ([64.233.182.184]:46998 "EHLO nf-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753482AbZCBQaB (ORCPT ); Mon, 2 Mar 2009 11:30:01 -0500 MIME-Version: 1.0 In-Reply-To: <20090302082003.1bb7bdc5@infradead.org> References: <1234722028-8110-1-git-send-email-andr345@gmail.com> <200902181528.29697.rusty@rustcorp.com.au> <1234952753.10531.48.camel@andreas-laptop> <1235216636.7025.1023.camel@andreas-laptop> <1236004353.10055.49.camel@andreas-laptop> <20090302082003.1bb7bdc5@infradead.org> Date: Mon, 2 Mar 2009 17:29:57 +0100 Message-ID: Subject: Re: [RFC PATCH 0/6] module, kbuild: Faster boot with custom kernel. From: Kay Sievers To: Arjan van de Ven Cc: Andreas Robinson , Rusty Russell , sam@ravnborg.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1532 Lines: 40 On Mon, Mar 2, 2009 at 17:20, Arjan van de Ven wrote: >> A monolithic kernel with parallelized initcalls is better - about 200 >> ms faster than parallel insmods on my test system. However, it comes >> with a fairly large set of changes: >> >> * First, you need a 200-line patch in init/main.c (do_initcalls() and >> friends) > > why? > We already have async function calls; and those speed up my boot (when > enabled) significantly, by doing much of the kernel/driver init in > parallel. > > My server box boots the whole kernel (including all drivers; I build > verything in) in 0.56 seconds, and my net books do it in around 1.0 > seconds. > >> >> * Then the built-in module dependencies must be calculated properly, >> eg with a modified depmod, and added to the build process. > > nope not if done right > >> So, what do you think, should I keep going? IMHO, the slower userspace >> implementation is acceptable since it's so much simpler. > > I would strongly suggest that you turn on the async function calls and > look at the boot graph of the resulting kernel boot... if you send > that to me I can also take a look and make suggestions.... The "fastboot" kernel commandline option was used, as mentioned in the mail. Is there anything else? Thanks, Kay -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/