IOSTAT(8) | System Manager's Manual | IOSTAT(8) |
iostat
—
iostat |
[-CdDITxyz ] [-c
count] [-H
height] [-W
width] [-w
wait] [drives] |
iostat
displays kernel I/O statistics on terminal, disk
and CPU operations. By default, iostat
displays one
line of statistics averaged over the machine's run time. The use of
-c
or -w
presents successive
lines averaged over the wait period. The
-I
option causes iostat
to
print raw, unaveraged values (totals).
Only the last disk option specified (-d
,
-D
, -x
, or
-y
) is used.
The options are as follows:
-c
count-I
flag is in effect, the first display is for the
time since a reboot and each subsequent report is for the time period
since the last display. If no wait interval is
specified, the default is 1 second.-C
-d
, -D
,
-T
, -x
, or
-y
flags are used.-d
-D
-I
). Use of this flag disables the default
display.-H
heightLINES
if set, or from the
terminal (window) size, if output is to a terminal and its size is set,
and otherwise defaults to 20. If explicitly set to zero, pages are
considered to be infinitely long. This parameter determines the frequency
at which repeated headers are output. If the value is greater than zero,
but too small for the header, along with one output set, then a new header
will be produced for each set of output.-I
-T
-C
, -d
,
-D
, -x
, or
-y
flags are used.-w
wait-W
widthCOLUMNS
if set, or from the
terminal (window) size, if output is to a terminal and its size is set,
and otherwise defaults to 80. If explicitly set to 0, lines are considered
infinitely long. This width is used only to determine the number of drives
to display by default when no drive list is given. In other cases output
will be as wide as needed to display the data requested.-x
-C
and
-T
options are ignored with this output
format.-y
-x
) and
additional queuing statistics. Output does not fit in an 80 column window.
The -C
and -T
options are
ignored with this output format.-z
-I
, has never done
any I/O.iostat
displays its information in the
following format:
iostat
displays only those drives that
fit on the display. To force iostat
to display
specific drives, they may be supplied on the command line, either as names
or fnmatch
() patterns.
The alternative display format, (selected with
-D
), presents the following values:
With the -y
flag, the following
queuing measurements are added:
Note that because of rounding, these percentages may appear to total more or less than 100.
The sections starting with ``Interpreting system activity'' in Installing and Operating 4.3BSD.
iostat
appeared in Version 6
AT&T UNIX. The -x
option was added in
NetBSD 1.4. Collection of queuing values and the
-y
option were added in NetBSD
8.0. The archaic option format:
iostat
[drives ...]
[wait [count]]
June 18, 2022 | NetBSD 10.0 |