Hi, First off all to use more than 64 CPUs on Windows you should use CPU grouping. Each group can contain maximum 64 CPUs. Here is a good article explaining possible configurations: https://msdn.microsoft.com/en-us/windows/hardware/drivers/devtest/boot-parameters-to-test-drivers-for-multiple-processor-group-support <https://msdn.microsoft.com/en-us/windows/hardware/drivers/devtest/boot-parameters-to-test-drivers-for-multiple-processor-group-support> and another one on the grouping subject: https://blogs.technet.microsoft.com/mlucas/2012/03/15/windows-server-and-processor-cores/ <https://blogs.technet.microsoft.com/mlucas/2012/03/15/windows-server-and-processor-cores/>
Regarding the boot failure - it is quite possible that Windows cannot handle more that 64 logical CPUs on one physical CPU. Best regards, Yan. > On 9 Feb 2017, at 08:18, hangaohuai <hangaoh...@huawei.com> wrote: > > Dear all: > I try to boot windows2012R2 (more than 64 cores)on kvm platform with hyper-v > on*<relaxed state='on'/>*. > the guest halts on the starting time. > Also tested in these cases: > <topology sockets='64' cores='1' threads='1'/> - boot sucess > <topology sockets='1' cores='64' threads='1'/> - boot sucess > <topology sockets='1' cores='1' threads='64'/> - boot sucess > <topology sockets='1' cores='68' threads='1'/> - boot failed > <topology sockets='68' cores='1' threads='1'/> - boot sucess(in Guest we can > found 64) > <topology sockets='1' cores='1' threads='68'/> - boot failed > > Environment: > GUEST: > windows2012R2 > HOST: > kernel version:4.10.0-rc4 > QEMU version:QEMU emulator version 2.8.50 (v2.8.0-664-gd1c82f7-dirty) > part of GuestXML: > <vcpu placement='static'>68</vcpu> > <resource> > <partition>/machine</partition> > </resource> > <os> > <type arch='x86_64' machine='pc-i440fx-2.3'>hvm</type> > <boot dev='hd'/> > </os> > <features> > <acpi/> > <apic/> > <pae/> > <hyperv> > <relaxed state='on'/> > </hyperv> > </features> > <cpu> > <topology sockets='1' cores='68' threads='1'/> > </cpu> > > ////////////////////////////////// > debug info: > virsh qemu-monitor-command win2012 --hmp "info cpus" > CPU #61: pc=0xfffff8031296a21c thread_id=21410 > CPU #62: pc=0xfffff8031296a21c thread_id=21411 > CPU #63: pc=0xfffff8031296a21c thread_id=21414 > CPU #64: pc=0x00000000000fd31c (halted) thread_id=21415 > CPU #65: pc=0x00000000000fd31c (halted) thread_id=21416 > CPU #66: pc=0x00000000000fd31c (halted) thread_id=21417 > CPU #67: pc=0x00000000000fd31c (halted) thread_id=21418 > > > Any suggestions? > > Thanks a lot. > > Gaohuai Han > >
