From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kevin Shanahan Subject: Re: XP smp using a lot of CPU Date: Thu, 14 May 2009 23:40:19 +0930 Message-ID: <20090514141018.GG5146@kulgan> References: <1242175298.15140.12.camel@iron.psg.net> <4A0A6F12.9000909@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Ross Boylan , kvm@vger.kernel.org To: Avi Kivity Return-path: Received: from bowden.ucwb.org.au ([203.122.237.119]:45424 "EHLO mail.ucwb.org.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752458AbZENOaV (ORCPT ); Thu, 14 May 2009 10:30:21 -0400 Content-Disposition: inline In-Reply-To: <4A0A6F12.9000909@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Wed, May 13, 2009 at 09:56:18AM +0300, Avi Kivity wrote: > Ross Boylan wrote: >> I just installed XP into a new VM, specifying -smp 2 for the machine. >> According to top, it's using nearly 200% of a cpu even when I'm not >> doing anything. >> >> Is this real CPU useage, or just a reporting problem (just as my disk >> image is big according to ls, but isn't really)? >> >> If it's real, is there anything I can do about it? >> >> kvm 0.7.2 on Debian Lenny (but 2.6.29 kernel), amd64. Xeon chips; 32 >> bit version of XP pro installed, now fully patched (including the >> Windows Genuine Advantage stuff, though I cancelled it when it wanted to >> run). >> >> Task manager in XP shows virtually no CPU useage. >> >> Please cc me on responses. >> >> > > I'm guessing Windows uses a pio port to sleep, which kvm doesn't > support. Can you provide kvm_stat output? Could this be what has happened to Windows 2000 as well? (kvm-Bugs-2314737) Task manager in the guest shows both CPUs idle, but on the host it shows 200% CPU almost constantly. ucwb-0119:/home/kmshanah/kvm/kvm-85# ./kvm_stat -1 efer_reload 0 0 exits 5454894602 4839 fpu_reload 5311150 5 halt_exits 200719 1 halt_wakeup 200218 1 host_state_reload 1951410204 1869 hypercalls 0 0 insn_emulation 1391377570 1393 insn_emulation_fail 52 0 invlpg 92034019 1 io_exits 1042421930 694 irq_exits 1545221935 1874 irq_injections 450100320 448 irq_window 225291775 245 kvm_request_irq 0 0 largepages 0 0 mmio_exits 484805 0 mmu_cache_miss 26346459 4 mmu_flooded 21532314 4 mmu_pde_zapped 886970 0 mmu_pte_updated 52882039 4 mmu_pte_write 70044961 6 mmu_recycled 1102 0 mmu_shadow_zapped 26384127 4 mmu_unsync 7671 0 mmu_unsync_global 0 0 nmi_injections 0 0 nmi_window 0 0 pf_fixed 421444565 167 pf_guest 34545643 1 remote_tlb_flush 125039581 9 request_nmi 0 0 signal_exits 1 0 tlb_flush 749126829 284 Regards, Kevin.