From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcus White Subject: Re: Date: Thu, 17 Apr 2014 14:33:41 -0700 Message-ID: References: <20140416211734.GA15155@amt.cnet> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: kvm To: Marcelo Tosatti Return-path: Received: from mail-ve0-f193.google.com ([209.85.128.193]:33068 "EHLO mail-ve0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751312AbaDQVdm (ORCPT ); Thu, 17 Apr 2014 17:33:42 -0400 Received: by mail-ve0-f193.google.com with SMTP id oz11so272498veb.0 for ; Thu, 17 Apr 2014 14:33:41 -0700 (PDT) In-Reply-To: <20140416211734.GA15155@amt.cnet> Sender: kvm-owner@vger.kernel.org List-ID: >> > Hello, >> > I had some basic questions regarding KVM, and would appreciate any help:) >> > >> > I have been reading about the KVM architecture, and as I understand >> > it, the guest shows up as a regular process in the host itself.. >> > >> > I had some questions around that.. >> > >> > 1. Are the guest processes implemented as a control group within the >> > overall VM process itself? Is the VM a kernel process or a user >> > process? > > User process. > >> > 2. Is there a way for me to force some specific CPU/s to a guest, and >> > those CPUs to be not used for any work on the host itself? Pinning is >> > just making sure the vCPU runs on the same physical CPU always, I am >> > looking for something more than that.. > > Control groups. Do control groups prevent the host from using those CPUs? I want only the VM to use the CPUs, and dont want any host user or kernel threads to run on that physical CPU. I looked up control groups, maybe I missed something there. I will go back and take a look. If you can clarify, I would appreciate it:) > >> > 3. If the host is compiled as a non pre-emptible kernel, kernel >> > process run to completion until they give up the CPU themselves. In >> > the context of a guest, I am trying to understand what that would mean >> > in the context of KVM and guest VMs. If the VM is a user process, it >> > means nothing, I wasnt sure as per (1). > > What problem are you trying to solve? Its more of an investigation at this point to understand what can happen..