virtiostat - Trace VIRTIO devices input/output statistics. Uses Linux eBPF/bcc. virtiostat [-h] [-T] [-D] [-d DRIVER] [-n DEVNAME] [INTERVAL] [COUNT] This tool traces VIRTIO devices input/output statistics. It works in lower layer of VIRTIO base driver, so it could trace all the devices of VIRTIO family. For example, we can't get IO statistics of 9p-fs in a guest virtual machine by iostat command, but we can analyze IO statistics by virtiostat. The outputing result shows In/Out SGs(scatter list operation) to represent positive correlation IOPS, and In/Out BW to represent throughput. Since this uses BPF, only the root user can use this tool. CONFIG_BPF and bcc.

-h Print usage message.

-T Include a time column on output (HH:MM:SS).

-D Show debug infomation of bpf text.

-d DRIVER Filter for driver name.

-n DEVNAME Filter for device name.

INTERVAL Print output every interval seconds.

COUNT Total count of trace in seconds.

Trace virtio device statistics and print 1 second summaries, 10 times: # virtiostat 1 10

Trace virtio block deivces only: # virtiostat -d virtio_blk

This traces the kernel virtqueue_add_sgs, virtqueue_add_outbuf, virtqueue_add_inbuf, virtqueue_add_inbuf_ctx functions. The rate of this depends on all the VIRTIO devices IOPS. This is from bcc. https://github.com/iovisor/bcc

Also look in the bcc distribution for a companion _examples.txt file containing example usage, output, and commentary for this tool.

Linux Unstable - in development. zhenwei pi iostat(1), iftop(8), funccount(8)