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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 185CEC2BABC for ; Tue, 7 Apr 2020 09:26:48 +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 AC1E9206C0 for ; Tue, 7 Apr 2020 09:26:47 +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="GJizmHP2" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AC1E9206C0 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]:43894 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jLkVK-0001I4-Ps for qemu-devel@archiver.kernel.org; Tue, 07 Apr 2020 05:26:46 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:33352) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jLkRi-0003R4-5A for qemu-devel@nongnu.org; Tue, 07 Apr 2020 05:23:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1jLkRh-0001FW-2z for qemu-devel@nongnu.org; Tue, 07 Apr 2020 05:23:02 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:45512 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1jLkRg-0001F6-VK for qemu-devel@nongnu.org; Tue, 07 Apr 2020 05:23:01 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1586251380; h=from:from:reply-to: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=1bIkcehhb7OPhwm/zxUQzVJyR7RK05NU6I+4eyQpuVY=; b=GJizmHP2aWsxzduVNa04PzA+vR5wgfctKyAk0yUqPOtyN3xIHGhYNYuP0StB1/vTYjZBOH BXqKcYzqH5D4yn5WoJHYz7MCF6R8xaVr4cC+MEBQ0NWYSvFvxPVZbgfgpJF5/B/xXdBqhZ 9r5yuLMuTex4kd2QIredgUO8IbjLKaY= 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-37-3dsuHItdP-OWujVKGAC3Xg-1; Tue, 07 Apr 2020 05:22:53 -0400 X-MC-Unique: 3dsuHItdP-OWujVKGAC3Xg-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 374FE800D50; Tue, 7 Apr 2020 09:22:52 +0000 (UTC) Received: from redhat.com (unknown [10.36.110.60]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 7B7749D37E; Tue, 7 Apr 2020 09:22:50 +0000 (UTC) Date: Tue, 7 Apr 2020 10:22:46 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: gokul cg Subject: Re: X86: Abnormal variation in Freebsd VM launch time w.r.t freebsd guest config Message-ID: <20200407092246.GC843246@redhat.com> References: MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.13.3 (2020-01-12) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.120 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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Cc: qemu-devel@nongnu.org, qemu-discuss@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, Apr 07, 2020 at 09:59:59AM +0530, gokul cg wrote: > Hi Team, >=20 > We are observing abnormal variation in VM launch time w.r.t guest config. >=20 > A simple VM(2gb ram no passthrough device) creation takes usually 6sec > (Time from execution of 'virsh create guest.xml to get print "Welcome to > FreeBSD"' ),but when we add a USB passthrough device launch time increase= d > to 18-19 sec and further increased to 39-44sec when we have increased gue= st > ram to 48Gb. snip. > Note : 1) This we have seen with legacy pci passthrough device not with > vfio. And we have not noticed any perfoance impact other than qemu-init/v= m > laucn time . Legacy pci passthrough support was deleted way back to 2017, and we had deprecated it for 2 years before then, in favour of VFIO. > Any suggestions to improve launch time with legacy passthrough ? Just stop using legacy PCI assignment. VFIO has been the recommended impl for 5+ years now. Regards, Daniel --=20 |: https://berrange.com -o- https://www.flickr.com/photos/dberrange= :| |: https://libvirt.org -o- https://fstop138.berrange.com= :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange= :|