[libvirt] strange behavior when using iotune

Hi. I'm try to shape disk via total_iops_sec in libvirt libvirt 1.2.10 qemu 2.0.0 Firstly when i'm run vm with predefined <total_iops_sec>5000</total_iops_sec> i have around 11000 iops (dd if=/dev/sda bs=512K of=/dev/null) After that i'm try to set via virsh --total_iops_sec 10 to want to minimize io, but nothing changed. After that i'm reboot vm with <total_iops_sec>10</total_iops_sec> and get very slow io, but this expected. But libvirt says that i have is around 600 iops. My questions is - why i can't change total_iops_sec in run-time, and why entered values does not equal values getting from libvirt ? Thanks for any suggestions and any help. -- Vasiliy Tolstov, e-mail: v.tolstov(a)selfip.ru jabber: vase(a)selfip.ru