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.
Print usage message.
Include a time column on output (HH:MM:SS).
Show debug infomation of bpf text.
- -d DRIVER
Filter for driver name.
- -n DEVNAME
Filter for device name.
Print output every interval seconds.
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.
Also look in the bcc distribution for a companion _examples.txt file containing example usage, output, and commentary for this tool.
Unstable - in development.
iostat(1), iftop(8), funccount(8)