From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 83365C4332E for ; Mon, 23 Mar 2020 12:18:19 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5172E20789 for ; Mon, 23 Mar 2020 12:18:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="VvJtJbHY" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5172E20789 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:33016 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jGM26-0002rJ-HZ for qemu-devel@archiver.kernel.org; Mon, 23 Mar 2020 08:18:18 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48468) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jGM17-0002GX-5P for qemu-devel@nongnu.org; Mon, 23 Mar 2020 08:17:18 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1jGM15-0001p5-OU for qemu-devel@nongnu.org; Mon, 23 Mar 2020 08:17:16 -0400 Received: from us-smtp-delivery-74.mimecast.com ([63.128.21.74]:60413) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1jGM15-0001nF-Dg for qemu-devel@nongnu.org; Mon, 23 Mar 2020 08:17:15 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1584965833; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=z3fbYg3maC1qi4M4XPzuVn3hSbuRPPqu7+mZ2lsje+Y=; b=VvJtJbHYwLigb7TWzDdFDpLsoEDXBQuQZxedBZjhT/ozxJ/AOcYyx5FjPllf1H5bxBDGcy YKc+uyevbUrGw4Emni0la8V+sCQzZF3h7UU7A8tc2JgNYXfywyAK6q1AKDkwe341BgRJ0s dUZJPWRS8g6/CHTsSamsw9v2oeZK3xM= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-448-nrRDyc2jOTywoiq7OztsQg-1; Mon, 23 Mar 2020 08:17:11 -0400 X-MC-Unique: nrRDyc2jOTywoiq7OztsQg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id EFC8A8017CE; Mon, 23 Mar 2020 12:17:10 +0000 (UTC) Received: from localhost (unknown [10.40.208.31]) by smtp.corp.redhat.com (Postfix) with ESMTP id 08EB05E240; Mon, 23 Mar 2020 12:17:00 +0000 (UTC) Date: Mon, 23 Mar 2020 13:16:58 +0100 From: Igor Mammedov To: Gerd Hoffmann Subject: Re: [PATCH 00/13] microvm: add acpi support Message-ID: <20200323131658.30152128@redhat.com> In-Reply-To: <20200323120948.f6egd7rhfso6276p@sirius.home.kraxel.org> References: <20200319080117.7725-1-kraxel@redhat.com> <20200323065050-mutt-send-email-mst@kernel.org> <20200323120948.f6egd7rhfso6276p@sirius.home.kraxel.org> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 63.128.21.74 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eduardo Habkost , Sergio Lopez , "Michael S. Tsirkin" , qemu-devel@nongnu.org, Paolo Bonzini , Richard Henderson Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, 23 Mar 2020 13:09:48 +0100 Gerd Hoffmann wrote: > On Mon, Mar 23, 2020 at 06:51:10AM -0400, Michael S. Tsirkin wrote: > > On Thu, Mar 19, 2020 at 09:01:04AM +0100, Gerd Hoffmann wrote: > > > I know that not supporting ACPI in microvm is intentional. If you still > > > don't want ACPI this is perfectly fine, you can use the usual -no-acpi > > > switch to toggle ACPI support. > > > > > > These are the advantages you are going to loose then: > > > > > > (1) virtio-mmio device discovery without command line hacks (tweaking > > > the command line is a problem when not using direct kernel boot). > > > (2) Better IO-APIC support, we can use IRQ lines 16-23. > > > (3) ACPI power button (aka powerdown request) works. > > > (4) machine poweroff (aka S5 state) works. > > > > What is the cost though? How do boot times compare? > > Well, acpi speeds up booting by one second because this delay ... > > [ 0.275736] i8042: PNP: No PS/2 controller found. > [ 0.275736] i8042: Probing ports directly. > [ 1.315447] i8042: No controller found > > ... goes away, at least with standard distro kernels. When building > your own you can probably compile out the driver somehow, even though > something seems to select SERIO_I8042 so trying to simply flip > CONFIG_SERIO_I8042 to 'n' in .config doesn't work. And a runtime > switch seems to not be there either ... > > So that ruined my plan to just time until the root filesystem is > mounted. Decided to use the "i8042: PNP: No PS/2 controller found." > line instead for a simple test (just check the kernel log timestamps, > three runs each). The ACPI initialization is already done at that > point, so it should be useful nevertheless. Here we go: > > Without acpi: > 0.277710 > 0.278852 > 0.279520 > > With acpi: > 0.283917 > 0.284262 > 0.284836 I wonder what would be difference with hw-reduced acpi > So the difference is less than 0.01 seconds on my box. > > cheers, > Gerd >