-c Display the CPU utilization report.
-d Display the device utilization report.
--dec={ 0 | 1 | 2 }
Specify the number of decimal places to use (0 to 2,
default value is 2).
-f directory
+f directory
Specify an alternative directory for iostat to read
devices statistics. Option -f tells iostat to use only the
files located in the alternative directory, whereas option
+f tells it to use both the standard kernel files and the
files located in the alternative directory to read device
statistics.
directory is a directory containing files with statistics
for devices managed in userspace. It may contain:
- a "diskstats" file whose format is compliant with that
located in "/proc",
- statistics for individual devices contained in files
whose format is compliant with that of files located in
"/sys".
In particular, the following files located in directory
may be used by iostat:
directory/block/device/stat
directory/block/device/partition/stat
partition files must have an entry in directory/dev/block/
directory, e.g.:
directory/dev/block/major:minor -->
../../block/device/partition
-g group_name { device [...] | ALL }
Display statistics for a group of devices. The iostat
command reports statistics for each individual device in
the list then a line of global statistics for the group
displayed as group_name and made up of all the devices in
the list. The ALL keyword means that all the block devices
defined by the system shall be included in the group.
-H This option must be used with option -g and indicates that
only global statistics for the group are to be displayed,
and not statistics for individual devices in the group.
-h This option is equivalent to specifying --human --pretty.
--human
Print sizes in human readable format (e.g. 1.0k, 1.2M,
etc.) The units displayed with this option supersede any
other default units (e.g. kilobytes, sectors...)
associated with the metrics.
-j { ID | LABEL | PATH | UUID | ... } [ device [...] | ALL ]
Display persistent device names. Keywords ID, LABEL, etc.
specify the type of the persistent name. These keywords
are not limited, only prerequisite is that directory with
required persistent names is present in /dev/disk.
Optionally, multiple devices can be specified in the
chosen persistent name type. Because persistent device
names are usually long, option --pretty is implicitly set
with this option.
-k Display statistics in kilobytes per second.
-m Display statistics in megabytes per second.
-N Display the registered device mapper names for any device
mapper devices. Useful for viewing LVM2 statistics.
-o JSON
Display the statistics in JSON (Javascript Object
Notation) format. JSON output field order is undefined,
and new fields may be added in the future.
-p [ { device[,...] | ALL } ]
Display statistics for block devices and all their
partitions that are used by the system. If a device name
is entered on the command line, then statistics for it and
all its partitions are displayed. Last, the ALL keyword
indicates that statistics have to be displayed for all the
block devices and partitions defined by the system,
including those that have never been used. If option -j is
defined before this option, devices entered on the command
line can be specified with the chosen persistent name
type.
--pretty
Make the Device Utilization Report easier to read by a
human.
-s Display a short (narrow) version of the report that should
fit in 80 characters wide screens.
-t Print the time for each report displayed. The timestamp
format may depend on the value of the S_TIME_FORMAT
environment variable (see below).
-V Print version number then exit.
-x Display extended statistics.
-y Omit first report with statistics since system boot, if
displaying multiple records at given interval.
-z Tell iostat to omit output for any devices for which there
was no activity during the sample period.
