Michal Privoznik <mprivozn <at> redhat.com> writes: > > On 10.06.2015 01:05, Vivi L wrote: > > Kashyap Chamarthy <kchamart <at> redhat.com> writes: > > > > > >> You might want re-test by explicitly setting the 'page' element and > >> 'size' attribute? From my test, I had something like this: > >> > >> $ virsh dumpxml f21-vm | grep hugepages -B3 -A2 > >> <memory unit='KiB'>2000896</memory> > >> <currentMemory unit='KiB'>2000000</currentMemory> > >> <memoryBacking> > >> <hugepages> > >> <page size='2048' unit='KiB' nodeset='0'/> > >> </hugepages> > >> </memoryBacking> > >> <vcpu placement='static'>8</vcpu> > >> > >> I haven't tested this exhaustively, but some basic test notes here: > >> > >> https://kashyapc.fedorapeople.org/virt/test-hugepages-with-libvirt.txt > > > > Current QEMU does not support setting <page> element. Could it be the > > cause of my aforementioned problem? > > > > unsupported configuration: huge pages per NUMA node are not supported > > with this QEMU > > > > So this is explanation why the memory for you guest is not backed by > hugepages.
I thought setting hugepages per NUMA node is a nice-to-have feature. Is it required to enable the use of hugepages for the guest? > Can you please share the qemu command line that libvirt generated for > your guest? If setting 100 hugepages, the guest can start while not using hugepages at all. In this case, [root@local ~]# ps -ef | grep qemu qemu 3403 1 99 17:42 ? 00:36:42 /usr/libexec/qemu-kvm -name qvpc-di-03-sf -S -machine pc-i440fx-rhel7.0.0,accel=kvm,usb=off -cpu host -m 131072 -realtime mlock=off -smp 32,sockets=2,cores=16,threads=1 -numa node,nodeid=0,cpus=0-15,mem=65536 -numa node,nodeid=1, cpus=16-31,mem=65536 -uuid e1b72349-4a0b-4b91-aedc-fd34e92251e4 - smbios type=1,serial=SCALE-SLOT-03 -no-user-config -nodefaults -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/qvpc-di-03-sf.monitor,server, nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=utc -no-shutdown -boot strict=on -device piix3-usb-uhci,id=usb,bus=pci.0, addr=0x1.0x2 -drive file=/var/lib/libvirt/images/asr5700/qvpc-di-03-sf- hda.img,if=none,id=drive-ide0-0-0,format=qcow2 -device ide- hd,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0,bootindex=2 -drive if=none,id=drive-ide0-1-0,readonly=on,format=raw -device ide- cd,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0,bootindex=1 -chardev pty,id=charserial0 -device isa-serial,chardev=charserial0,id=serial0 -chardev pty,id=charserial1 -device isa-serial,chardev=charserial1,id=serial1 -vnc 127.0.0.1:0 -vga cirrus -device i6300esb,id=watchdog0,bus=pci.0, addr=0x3 -watchdog-action reset -device vfio-pci,host=08:00.0,id=hostdev0,bus=pci.0,addr=0x5 -device vfio- pci,host=09:00.0,id=hostdev1,bus=pci.0,addr=0x6 -device vfio- pci,host=0a:00.0,id=hostdev2,bus=pci.0,addr=0x7 -device virtio-balloon- pci,id=balloon0,bus=pci.0,addr=0x4 -msg timestamp=on > Michal > > -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
