How virtio-blk latency can be measured

hi,I want to calculate the latencyof virtio in kvm, I read the document in http://www.linux-kvm.org/page/Virtio/Block/Latency and met some problem.
1. when calculating latency in kvm, the document said kvm_pio and kvm_set_irq can be filtered using command 'lspci -vv -nn' and 'cat /proc/interrupts' , but I don't know how to use the result to filter kvm_pio and kvm_set_irq.
2. Anyone know who is the author of this webpage:
http://www.linux-kvm.org/page/Virtio/Block/Latency .
Thank you.