Section 8 · System administration

bcc-virtiostat.8

Package: bcc-tools

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virtiostat

NAME
SYNOPSIS
DESCRIPTION
REQUIREMENTS
OPTIONS
EXAMPLES
OVERHEAD
SOURCE
OS
STABILITY
AUTHOR
SEE ALSO

NAME

virtiostat − Trace VIRTIO devices input/output statistics. Uses Linux eBPF/bcc.

SYNOPSIS

virtiostat [−h] [−T] [−D] [-d DRIVER] [-n DEVNAME] [INTERVAL] [COUNT]

DESCRIPTION

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.

REQUIREMENTS

CONFIG_BPF and bcc.

OPTIONS


	−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.

EXAMPLES

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

virtiostat 1 10

Trace virtio block deivces only:

virtiostat -d virtio_blk

OVERHEAD

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.

SOURCE

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.

OS

Linux

STABILITY

Unstable - in development.

AUTHOR

zhenwei pi