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=-6.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 2A40AC43468 for ; Mon, 21 Sep 2020 14:12:03 +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 A915520B1F for ; Mon, 21 Sep 2020 14:12:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="O5Lb2aTV" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A915520B1F 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]:33446 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kKMXx-0007du-LA for qemu-devel@archiver.kernel.org; Mon, 21 Sep 2020 10:12:01 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:39440) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kKMVy-00067m-Pl for qemu-devel@nongnu.org; Mon, 21 Sep 2020 10:10:00 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:46643) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kKMVu-0000Q2-5Q for qemu-devel@nongnu.org; Mon, 21 Sep 2020 10:09:56 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1600697392; 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=sFbaDCKyhtAolPKogznx7buXOckNJ3eKUugLxLMHalA=; b=O5Lb2aTVOBCCvEdmRzNHhmRXOEn0kQvoo83Sg1iR87/YUu6Mg3jIcOdYSee7P5Hv230Ksh ZZKQBWeHScoH0K2e3oBxEFXSOehm3JqQEBsJ6DaZ7g2OnVPVMc8JyiDiXN4Y4p5rJqOS/H Enr+9QhdgILmgeWe6z+GwmGWrsb0znE= 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-148-RNwxcw1ZOeK_V6wfnp5bZA-1; Mon, 21 Sep 2020 10:09:50 -0400 X-MC-Unique: RNwxcw1ZOeK_V6wfnp5bZA-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 128B4801AE1; Mon, 21 Sep 2020 14:09:49 +0000 (UTC) Received: from redhat.com (ovpn-113-113.ams2.redhat.com [10.36.113.113]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2CE7210013D0; Mon, 21 Sep 2020 14:09:48 +0000 (UTC) Date: Mon, 21 Sep 2020 15:09:45 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Peter Lieven Subject: Re: Limiting per vCPU Usage Message-ID: <20200921140945.GO1942072@redhat.com> References: <68336702-cedc-dc38-3d18-d153cd7652dd@kamp.de> <20200921082950.GF1942072@redhat.com> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.14.6 (2020-07-11) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=berrange@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Content-Disposition: inline Received-SPF: pass client-ip=63.128.21.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/21 01:44:53 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -35 X-Spam_score: -3.6 X-Spam_bar: --- X-Spam_report: (-3.6 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.455, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action 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" Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, Sep 21, 2020 at 03:47:56PM +0200, Peter Lieven wrote: > Am 21.09.20 um 10:29 schrieb Daniel P. Berrangé: > > On Sun, Sep 20, 2020 at 10:24:41PM +0200, Peter Lieven wrote: > > > Hi Qemu folks, > > > > > > > > > is there a BCP to limit just the maximum usage of a virtual (KVM) cpu? > > > > > > I know that there are many approaches, but as far as I know they all limit the complete qemu process which is far more > > > > > > than just the virtual CPUs. > > > > > > Is it possible to limit just the vCPU threads and leave threads that > > > handle the monitor, vnc, qmp, iothreads, storage backend etc. > > Libvirt uses cgroups to achieve what you describe. A cgroup for the > > QEMU process as a whole, then create child cgroups, one for each > > vCPUs, and a further one for non-vCPU threads. CPU limits are then > > applied on the child cgroups. > > > Hi Daniel, > > > I came up with the same solution. Is there a nice way to get the thread ids of the vCPUs? > > Iterating over all thread IDs and check the names works, but the thread names are not considered > > a stable API (text from original commit message). The QMP query-cpus command tells you thread IDs. There is similar for I/O threads too. This is what libvirt uses to determine the mappings. Regards, Daniel -- |: 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 :|