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

SEE ALSO

       iostat(1), iftop(8), funccount(8)