-balloon virtio 弹性内存
# qemu-kvm -m 128 -smp 2 \
-drive file=/root/cirros-0.3.5-x86_64-disk.img,media=disk,format=qcow2,cache=writeback,if=virtio \
-nographic \
-net nic,model=virtio -net tap,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown
-daemonize 后台运行
# qemu-kvm -m 512 -smp 2 -name test \
-drive file=/root/centos.qcow2,media=disk,if=virtio,format=qcow2 \
-balloon virtio \
-net nic,model=virtio,macaddr=52:54:00:A5:41:1E -net tap,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown \
-daemonize
VNC server running on `::1:5900′
# vncviewer ::1:5900
-usbdevice tablet usb鼠标问题
# qemu-kvm -m 2G -smp 2 -name test \
-drive file=/root/cirros-0.3.5-x86_64-disk.img,media=disk,if=virtio,format=qcow2 \
-vnc 10.0.0.2:0,password -monitor stdio -balloon virtio \
-net nic,model=virtio,macaddr=52:54:00:A5:41:1E -net tap,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown \
-usbdevice tablet
virtio-net:
vhost-net:用于取代工作与用户空间的qemu中为virtio-net实现的后端驱动以实现性能提升的驱动
-net tap[,vnet_hdr=on|off][,vhost=on|off]
qemu-kvm -net tap,vnet_hdr=on,vhost=on
Host中的GSO,TSO
关掉会继续提升性能:
ethtool -K $IF gso off
ethtool -K $IF tso off
ethtool -K $IF
# lsmod | grep vhost
vhost_net 29168 1
macvtap 10900 1 vhost_net
tun 17094 3 vhost_net
# grep VHOST /boot/config-2.6.32-696.el6.x86_64
CONFIG_VHOST_NET=m
VM Migration:
static migration
live migration
服务迁移时间
服务器停机时间
对服务性能影响
在待迁入主机使用:
#qemu-kvm -vnc :N -incoming tcp:0:7777
# vncviewer :590N
在源主机使用:
monitor接口:
migrate tcp:DEST_IP:DEST:PORT
# qemu-kvm -m 2048 -smp 2 -name test \
-drive file=/root/centos.qcow2,format=qcow2,if=virtio,media=disk \
-balloon virtio -usbdevice tablet -daemonize -vnc 10.0.0.2:0 \
-net nic,model=virtio,macaddr=52:54:00:A5:41:1E \
-net tap,vnet_hdr=on,vhost=on,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown