From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Monjalon Subject: Re: [PATCH v4 00/10] VM Power Management Date: Mon, 13 Oct 2014 22:26:23 +0200 Message-ID: <3264386.kAdiTFhMft@xps13> References: <1412003903-9061-1-git-send-email-alan.carew@intel.com> <1413142571-23069-1-git-send-email-alan.carew@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: dev-VfR2kkLFssw@public.gmane.org To: Alan Carew Return-path: In-Reply-To: <1413142571-23069-1-git-send-email-alan.carew-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces-VfR2kkLFssw@public.gmane.org Sender: "dev" Hi Alan, 2014-10-12 20:36, Alan Carew: > The following patches add two DPDK sample applications and an alternate > implementation of librte_power for use in virtualized environments. > The idea is to provide librte_power functionality from within a VM to address > the lack of MSRs to facilitate frequency changes from within a VM. > It is ideally suited for Haswell which provides per core frequency scaling. > > The current librte_power affects frequency changes via the acpi-cpufreq > 'userspace' power governor, accessed via sysfs. Something was preventing me from looking deeper in this big codebase, but I didn't know what sounds weird. Now I realize: the real problem is that virtualization transparency is broken for power management. So the right thing to do is to fix it in KVM. I think all this patchset is a huge workaround. Did you try to fix it with Qemu/KVM? -- Thomas