From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mathieu Othacehe Subject: Re: 02/02: image: Disable compression for ISO images. Date: Mon, 27 Apr 2020 18:00:05 +0200 Message-ID: <87d07sx6ka.fsf@gmail.com> References: <20200427140924.28752.28126@vcs0.savannah.gnu.org> <20200427140926.3B6CF20B7A@vcs0.savannah.gnu.org> <87blndt116.fsf@nckx> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Return-path: Received: from eggs.gnu.org ([2001:470:142:3::10]:43518) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jT6B2-0007e6-3N for guix-devel@gnu.org; Mon, 27 Apr 2020 12:00:12 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.90_1) (envelope-from ) id 1jT6B1-00045Q-CS for guix-devel@gnu.org; Mon, 27 Apr 2020 12:00:11 -0400 Received: from mail-wm1-x329.google.com ([2a00:1450:4864:20::329]:37820) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jT6B0-00044g-UN for guix-devel@gnu.org; Mon, 27 Apr 2020 12:00:10 -0400 Received: by mail-wm1-x329.google.com with SMTP id z6so204508wml.2 for ; Mon, 27 Apr 2020 09:00:10 -0700 (PDT) In-Reply-To: <87blndt116.fsf@nckx> (Tobias Geerinckx-Rice's message of "Mon, 27 Apr 2020 17:13:18 +0200") List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+gcggd-guix-devel=m.gmane-mx.org@gnu.org Sender: "Guix-devel" To: Tobias Geerinckx-Rice Cc: Guix-devel Hey Tobias, > guix-commits@gnu.org =E5=86=99=E9=81=93=EF=BC=9A >> + ;; XXX: Temporarily disable compression to speed-up the tests. >> + (compression? #f))) > > Interesting! What kind of improvement do you see, roughly? I posted some figures here: https://lists.gnu.org/archive/html/guix-devel/2020-04/msg00374.html. Here's a more complete summary: --8<---------------cut here---------------start------------->8--- | | Host (wip-disk-image) | VM (master) | |----------------+-----------------------+-------------| | No compression | 4min | 12min | | Compression | 8min | 19min | --8<---------------cut here---------------end--------------->8--- > When I added zlib compression I was surprised to learn that here it made = no > significant difference in wall clock time (less than a minute; 5% or so) = or > CPU time. The disks they spin and CPU she is fast, but still I would have > noticed a spike. Strange we have different results, those benches are not very accurate though. Thanks, Mathieu