From mboxrd@z Thu Jan 1 00:00:00 1970 From: Richard Davies Subject: Re: Windows slow boot: contractor wanted Date: Mon, 20 Aug 2012 09:16:52 +0100 Message-ID: <20120820081652.GB12177@alpha.arachsys.com> References: <20120816104727.GA17166@alpha.arachsys.com> <502CDC0D.9080004@redhat.com> <20120817123642.GA16736@alpha.arachsys.com> <201208190002.48454.iggy@theiggy.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Avi Kivity , kvm@vger.kernel.org, qemu-devel@nongnu.org To: Brian Jackson Return-path: Content-Disposition: inline In-Reply-To: <201208190002.48454.iggy@theiggy.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org Sender: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org List-Id: kvm.vger.kernel.org Brian Jackson wrote: > Richard Davies wrote: > > The host in question has 128GB RAM and dual AMD Opteron 6128 (16 cores > > total). It is running kernel 3.5.1 and qemu-kvm 1.1.1. > > > > In this morning's test, we have 3 guests, all booting Windows with 40GB RAM > > and 8 cores each (we have seen small VMs go slow as I originally said, but > > it is easier to trigger with big VMs): > > > > pid 15665: qemu-kvm -nodefaults -m 40960 -smp 8 -cpu host,hv_relaxed \ > > -vga cirrus -usbdevice tablet -vnc :99 -monitor stdio -hda test1.raw > > pid 15676: qemu-kvm -nodefaults -m 40960 -smp 8 -cpu host,hv_relaxed \ > > -vga cirrus -usbdevice tablet -vnc :98 -monitor stdio -hda test2.raw > > pid 15653: qemu-kvm -nodefaults -m 40960 -smp 8 -cpu host,hv_relaxed \ > > -vga cirrus -usbdevice tablet -vnc :97 -monitor stdio -hda test3.raw > > What memory options have you tried? (KSM, hugepages, -mem-preallocate)? The host kernel has KSM and CONFIG_TRANSPARENT_HUGEPAGE=y and CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS=y. Our qemu-kvm command lines are as above, so we aren't using -mem-prealloc. We'll try that. > Is this only with 2008? (is that regular? R2?) It is intermittent. We definitely see it with 2008 R2, and I believe with 2008 as well. We don't have many customers running earlier versions of Windows. > Have you tried any of the hyperv features/hints? We have tried "-cpu host" and "-cpu host,hv_relaxed" as above, which both exhibit the bug. What other hyperv options do you think we should try? Richard.