From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753073Ab0BNVGQ (ORCPT ); Sun, 14 Feb 2010 16:06:16 -0500 Received: from mail.lang.hm ([64.81.33.126]:59820 "EHLO bifrost.lang.hm" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751543Ab0BNVGP (ORCPT ); Sun, 14 Feb 2010 16:06:15 -0500 Date: Sun, 14 Feb 2010 13:04:45 -0800 (PST) From: david@lang.hm X-X-Sender: dlang@asgard.lang.hm To: Stefan Richter cc: Pavel Machek , Jean Delvare , Willy Tarreau , mirrors@kernel.org, lasse.collin@tukaani.org, linux-kernel , users@kernel.org, "FTPAdmin Kernel.org" , Linus Torvalds Subject: Re: [kernel.org users] XZ Migration discussion In-Reply-To: <4B784378.8070309@s5r6.in-berlin.de> Message-ID: References: <4B744E13.8040004@kernel.org> <20100212150137.648dca7c@hyperion.delvare> <4B75A5DC.3060803@kernel.org> <20100212202357.6363d5af@hyperion.delvare> <20100212230702.GA10266@1wt.eu> <20100213091748.276821e1@hyperion.delvare> <20100214170724.GE1578@ucw.cz> <4B784378.8070309@s5r6.in-berlin.de> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 14 Feb 2010, Stefan Richter wrote: > Pavel Machek wrote: > [Jean Delvare wrote] >>> I have an old, slow machine here which I am going to use to perform >>> some real world testing, and I'll post the results when I'm done. But I >>> suspect that building a kernel on this machine, even a small one with >>> just the drivers it needs, will take much longer than unpacking the >>> sources. So anyone worrying about performance would rather rely on >>> cross-compilation, and in turn can afford whatever decompression tool >>> is needed. >> >> On zaurus, kernel compilation takes 4 hours. (I.e. "one night"). So >> that one is ... well ... done overnight. >> >> Untar is something I normally wait for, since you need to run >> (interactive) oldconfig after that. > > If the download takes m minutes and unpacking and unarchiving tar.gz > takes another n minutes, what difference does it make for this workflow > when instead m + p minutes are spent for download + unpacking and > unarchiving tar.bz2 or tar.xz? The difference is that the user is waiting for the n or m minutes, but goes off and does something else for the p minutes. So it doesn't really matter if the compile takes 1 hour or 6 hours. As Pavel noted, this is done overnight and it doesn't matter if it gets done at 2am or 6am. But the uncompression has a user waiting for it (to do the config step), so here it makes a big difference if it takes 6 minutes ot 8 minutes. David Lang