From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:43654) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1T4AIl-0002U4-TE for qemu-devel@nongnu.org; Wed, 22 Aug 2012 08:44:57 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1T4AIk-0002k6-Um for qemu-devel@nongnu.org; Wed, 22 Aug 2012 08:44:51 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57600) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1T4AIk-0002jz-LI for qemu-devel@nongnu.org; Wed, 22 Aug 2012 08:44:50 -0400 Message-ID: <5034D437.8070106@redhat.com> Date: Wed, 22 Aug 2012 15:44:39 +0300 From: Avi Kivity MIME-Version: 1.0 References: <20120816104727.GA17166@alpha.arachsys.com> <502CDC0D.9080004@redhat.com> <20120817123642.GA16736@alpha.arachsys.com> <5030F273.5080706@redhat.com> <20120820135656.GA16676@alpha.arachsys.com> <50334E13.8020100@redhat.com> <20120821152107.GA16363@alpha.arachsys.com> <5034A18B.5040408@redhat.com> <20120822124032.GA12647@alpha.arachsys.com> In-Reply-To: <20120822124032.GA12647@alpha.arachsys.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] Windows slow boot: contractor wanted List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Richard Davies Cc: qemu-devel@nongnu.org, kvm@vger.kernel.org On 08/22/2012 03:40 PM, Richard Davies wrote: > > I can trigger the slow boots without KSM and they have the same profile, > with _raw_spin_lock_irqsave and isolate_freepages_block at the top. > > I reduced to 3x 20GB 8-core VMs on a 128GB host (rather than 3x 40GB 8-core > VMs), and haven't managed to get a really slow boot yet (>5 minutes). I'll > post agan when I get one. I think you can go higher than that. But 120GB on a 128GB host is pushing it. > > In the slowest boot that I have so far (1-2 minutes), this is the perf top > ouput: > > > PerfTop: 26741 irqs/sec kernel:97.5% exact: 0.0% [4000Hz cycles], (all, 16 CPUs) > --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- > > 53.94% [kernel] [k] clear_page_c > 2.77% [kernel] [k] svm_vcpu_put > 2.60% [kernel] [k] svm_vcpu_run > 1.79% [kernel] [k] sub_preempt_count > 1.56% [kernel] [k] svm_vcpu_load > 1.44% [kernel] [k] __schedule > 1.36% [kernel] [k] kvm_arch_vcpu_ioctl_run > 1.34% [kernel] [k] resched_task > 1.32% [kernel] [k] _raw_spin_lock > 0.98% [kernel] [k] trace_preempt_on > 0.95% [kernel] [k] get_parent_ip > 0.94% [kernel] [k] yield_to This is pretty normal, Widows is touching memory so clear_page_c() is called to scrub it. -- error compiling committee.c: too many arguments to function