Re: [libvirt-users] VMs fail to start with NUMA configuration

On 2013年01月28日 11:47, Osier Yang wrote: > > On 2013年01月28日 11:44, Osier Yang wrote: >> >> On 2013年01月26日 01:07, Doug Goldstein wrote: >>> >>> On Thu, Jan 24, 2013 at 12:58 AM, Osier Yang&lt;jyang(a)redhat.com&gt; wrote: >>>> >>>> On 2013年01月24日 14:26, Doug Goldstein wrote: >>>>> >>>>> >>>>> On Wed, Jan 23, 2013 at 11:02 PM, Osier Yang&lt;jyang(a)redhat.com&gt; wrote: >>>>>> >>>>>> >>>>>> On 2013年01月24日 12:11, Doug Goldstein wrote: >>>>>>> >>>>>>> >>>>>>> >>>>>>> On Wed, Jan 23, 2013 at 3:45 PM, Doug Goldstein&lt;cardoe(a)gentoo.org&gt; >>>>>>> wrote: >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> I am using libvirt 0.10.2.2 and qemu-kvm 1.2.2 (qemu-kvm 1.2.0 + >>>>>>>> qemu >>>>>>>> 1.2.2 applied on top plus a number of stability patches). Having >>>>>>>> issue >>>>>>>> where my VMs fail to start with the following message: >>>>>>>> >>>>>>>> kvm_init_vcpu failed: Cannot allocate memory >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> Smell likes we have problem on setting the NUMA policy (perhaps >>>>>> caused by the incorrect host NUMA topology), given that the system >>>>>> still has enough memory. Or numad (if it's installed) is doing >>>>>> something wrong. >>>>>> >>>>>> Can you see if there is something about the Nodeset used to set >>>>>> the policy in debug log? >>>>>> >>>>>> E.g. >>>>>> >>>>>> % cat libvirtd.debug | grep Nodeset >>>>> >>>>> >>>>> >>>>> Well I don't see anything but its likely because I didn't do something >>>>> correct. I had LIBVIRT_DEBUG=1 exported and ran libvirtd --verbose >>>>> from the command line. >>>> >>>> >>>> >>>> If the process is in background, it's expected you can't see anything >>>> >>>> >>>> My /etc/libvirt/libvirtd.conf had: >>>>> >>>>> >>>>> log_outputs="3:syslog:libvirtd 1:file:/tmp/libvirtd.log" But I didn't >>>>> get any debug messages. >>>> >>>> >>>> >>>> log_level=1 has to be set. >>>> >>>> Anyway, let's simply do this: >>>> >>>> % service libvirtd stop >>>> % LIBVIRT_DEBUG=1 /usr/sbin/libvirtd 2>&1 | tee -a libvirtd.debug >>>> >>> >>> That's what I was doing, minus the tee just to the console and nothing >>> was coming out. Which is why I added the 1:file:/tmp/libvirtd.log, >>> which also didn't get any debug messages. Turns out this instance must >>> have been built with --disable-debug, >>> >>> All I've got in the log is: >>> >>> # grep -i 'numa' libvirtd.debug >>> 2013-01-25 16:50:15.287+0000: 417: debug : virCommandRunAsync:2200 : >>> About to run /usr/bin/numad -w 2:2048 >>> 2013-01-25 16:50:17.295+0000: 417: debug : qemuProcessStart:3614 : >>> Nodeset returned from numad: 1 >> >> >> This looks right. >> >>> >>> Immediately below that is >>> >>> 2013-01-25 16:50:17.295+0000: 417: debug : qemuProcessStart:3622 : >>> Setting up domain cgroup (if required) >>> 2013-01-25 16:50:17.295+0000: 417: debug : virCgroupNew:619 : New >>> group /libvirt/qemu/bb-2.6.35.9-i686 >>> 2013-01-25 16:50:17.295+0000: 417: debug : virCgroupDetect:273 : >>> Detected mount/mapping 1:cpuacct at /sys/fs/cgroup/cpuacct in >>> 2013-01-25 16:50:17.295+0000: 417: debug : virCgroupDetect:273 : >>> Detected mount/mapping 2:cpuset at /sys/fs/cgroup/cpuset in >>> 2013-01-25 16:50:17.296+0000: 417: debug : virCgroupMakeGroup:537 : >>> Make group /libvirt/qemu/bb-2.6.35.9-i686 >>> 2013-01-25 16:50:17.296+0000: 417: debug : virCgroupMakeGroup:562 : >>> Make controller /sys/fs/cgroup/cpuacct/libvirt/qemu/bb-2.6.35.9-i686/ >>> 2013-01-25 16:50:17.296+0000: 417: debug : virCgroupMakeGroup:562 : >>> Make controller /sys/fs/cgroup/cpuset/libvirt/qemu/bb-2.6.35.9-i686/ >>> 2013-01-25 16:50:17.296+0000: 417: debug : virCgroupCpuSetInherit:469 >>> : Setting up inheritance /libvirt/qemu -> >>> /libvirt/qemu/bb-2.6.35.9-i686 >>> 2013-01-25 16:50:17.296+0000: 417: debug : virCgroupGetValueStr:361 : >>> Get value /sys/fs/cgroup/cpuset/libvirt/qemu/cpuset.cpus >>> 2013-01-25 16:50:17.296+0000: 417: debug : virFileClose:72 : Closed >>> fd 39 >>> 2013-01-25 16:50:17.296+0000: 417: debug : virCgroupCpuSetInherit:482 >>> : Inherit cpuset.cpus = 0-63 >>> 2013-01-25 16:50:17.296+0000: 417: debug : virCgroupSetValueStr:331 : >>> Set value >>> '/sys/fs/cgroup/cpuset/libvirt/qemu/bb-2.6.35.9-i686/cpuset.cpus' >>> to '0-63' >> >> >> This looks not right, it should be 0-7 instead. >> >>> 2013-01-25 16:50:17.296+0000: 417: debug : virFileClose:72 : Closed >>> fd 39 >>> 2013-01-25 16:50:17.296+0000: 417: debug : virCgroupGetValueStr:361 : >>> Get value /sys/fs/cgroup/cpuset/libvirt/qemu/cpuset.mems >>> 2013-01-25 16:50:17.296+0000: 417: debug : virFileClose:72 : Closed >>> fd 39 >>> 2013-01-25 16:50:17.296+0000: 417: debug : virCgroupCpuSetInherit:482 >>> : Inherit cpuset.mems = 0-7 >>> 2013-01-25 16:50:17.296+0000: 417: debug : virCgroupSetValueStr:331 : >>> Set value >>> '/sys/fs/cgroup/cpuset/libvirt/qemu/bb-2.6.35.9-i686/cpuset.mems' >>> to '0-7' >> >> >> This is right. >> >>> 2013-01-25 16:50:17.296+0000: 417: debug : virFileClose:72 : Closed >>> fd 39 >>> 2013-01-25 16:50:17.296+0000: 417: warning : qemuSetupCgroup:388 : >>> Could not autoset a RSS limit for domain bb-2.6.35.9-i686 >>> 2013-01-25 16:50:17.296+0000: 417: debug : virCgroupSetValueStr:331 : >>> Set value >>> '/sys/fs/cgroup/cpuset/libvirt/qemu/bb-2.6.35.9-i686/cpuset.mems' >>> to '1' >> >> >> And it's strange that the cpuset.mems is changed to '1' here. Oh, actually this is right, cpuset.mems is about the memory nodes. >> >>> 2013-01-25 16:50:17.296+0000: 417: debug : virFileClose:72 : Closed >>> fd 39 >>> >>> Could the RSS issue be related? Some kernel related option not playing >>> nice or enabled? > > > Instead, I'm wondering if the problem is caused by the mismatch > (from libvirt p.o.v) between cpuset.cpus and cpuset.mems, which > thus cause the problem for kernel memory management? So, the simple method to prove the guess is to use static placement like: <vcpu placement='static' cpuset='0-63'>2</vcpu> <numatune> <memory placement='static' nodeset='1'/> </numatune> Osier