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New page: IOSTAT(1M) UNIX Programmer's Manual IOSTAT(1M) == NAME == iostat - report I/O statistics == SYNOPSIS == iostat [ option ] ... [ interval [ count ] ] == D...

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IOSTAT(1M) UNIX Programmer's Manual IOSTAT(1M)

== NAME ==
iostat - report I/O statistics

== SYNOPSIS ==
iostat [ option ] ... [ interval [ count ] ]

== DESCRIPTION ==
_I_o_s_t_a_t delves into the system and reports certain statistics
kept about input-output activity. Information is kept about
up to three different disks (RF, RK, RP) and about termi-
nals. For each disk, IO completions and number of words
transferred are counted; for terminals collectively, the
number of input and output characters are counted. Also,
each sixtieth of a second, the state of each disk is exam-
ined and a tally is made if the disk is active. The tally
goes into one of four categories, depending on whether the
system is executing in user mode, in `nice' (background)
user mode, in system mode, or idle. From all these numbers
and from the known transfer rates of the devices it is pos-
sible to determine information such as the degree of IO
overlap and average seek times for each device.

The optional _i_n_t_e_r_v_a_l argument causes _i_o_s_t_a_t to report once
each _i_n_t_e_r_v_a_l seconds. The first report is for all time
since a reboot and each subsequent report is for the last
interval only.

The optional _c_o_u_n_t argument restricts the number of reports.

With no option argument _i_o_s_t_a_t reports for each disk the
number of transfers per minute, the milliseconds per average
seek, and the milliseconds per data transfer exclusive of
seek time. It also gives the percentage of time the system
has spend in each of the four categories mentioned above.

The following options are available:

-t Report the number of characters of terminal IO per
second as well.

-i Report the percentage of time spend in each of the four
categories mentioned above, the percentage of time each
disk was active (seeking or transferring), the percen-
tage of time any disk was active, and the percentage of
time spent in `IO wait:' idle, but with a disk active.

-s Report the raw timing information: 32 numbers indicat-
ing the percentage of time spent in each of the possi-
ble configurations of 4 system states and 8 IO states
(3 disks each active or not).

-b Report on the usage of IO buffers.

== FILES ==
/dev/kmem, /unix

[[Category:32v man section 1]]

@@ Line 4: / Line 4: @@
 == NAME ==
-     iostat - report I/O statistics
+iostat - report I/O statistics
 == SYNOPSIS ==
-     iostat [ option ] ...  [ interval [ count ] ]
+iostat [ option ] ...  [ interval [ count ] ]
 == DESCRIPTION ==
-     _I_o_s_t_a_t delves into the system and reports certain statistics
+'''Iostat''' delves into the system and reports certain statistics
-     kept about input-output activity.  Information is kept about
+kept about input-output activity.  Information is kept about
-     up to three different disks (RF, RK, RP) and about termi-
+up to three different disks (RF, RK, RP) and about terminals.  For each disk, IO completions and number of words
-     nals.  For each disk, IO completions and number of words
+transferred are counted; for terminals collectively, the
-     transferred are counted; for terminals collectively, the
+number of input and output characters are counted.  Also,
-     number of input and output characters are counted.  Also,
+each sixtieth of a second, the state of each disk is examined and a tally is made if the disk is active.  The tally
-     each sixtieth of a second, the state of each disk is exam-
+goes into one of four categories, depending on whether the
-     ined and a tally is made if the disk is active.  The tally
+system is executing in user mode, in `nice' (background)
-     goes into one of four categories, depending on whether the
+user mode, in system mode, or idle.  From all these numbers
-     system is executing in user mode, in `nice' (background)
+and from the known transfer rates of the devices it is possible to determine information such as the degree of IO
-     user mode, in system mode, or idle.  From all these numbers
+overlap and average seek times for each device.
-     The optional _i_n_t_e_r_v_a_l argument causes _i_o_s_t_a_t to report once
+The optional '''interval''' argument causes '''iostat''' to report once each '''interval''' seconds.  The first report is for  all time since a reboot and each subsequent report is for the last interval only.
-     The optional _c_o_u_n_t argument restricts the number of reports.
+The optional '''count''' argument restricts the number of reports.
-     With no option argument _i_o_s_t_a_t reports for each disk the
+With no option argument '''iostat''' reports for each disk the
-     number of transfers per minute, the milliseconds per average
+number of transfers per minute, the milliseconds per average
-     seek, and the milliseconds per data transfer exclusive of
+seek, and the milliseconds per data transfer exclusive of
-     seek time.  It also gives the percentage of time the system
+seek time.  It also gives the percentage of time the system
-     has spend in each of the four categories mentioned above.
+has spend in each of the four categories mentioned above.
-     The following options are available:
+The following options are available:
-     -t   Report the number of characters of terminal IO per
+-t   Report the number of characters of terminal IO per second as well.
-     -i   Report the percentage of time spend in each of the four
+-i   Report the percentage of time spend in each of the four categories mentioned above, the percentage of time each disk was active (seeking or transferring), the percentage of time any disk was active, and the percentage of time spent in `IO wait:' idle, but with a disk active.
-     -s   Report the raw timing information: 32 numbers indicat-
+-s   Report the raw timing information: 32 numbers indicating the percentage of time spent in each of the possible configurations of 4 system states and 8 IO states (3 disks each active or not).
-     -b   Report on the usage of IO buffers.
+-b   Report on the usage of IO buffers.
 == FILES ==
-     /dev/kmem, /unix
+/dev/kmem, /unix
 [[Category:32v man section 1]]

32v 1m iostat - Revision history

Neozeed at 19:44, 26 October 2009

Neozeed: New page: IOSTAT(1M) UNIX Programmer's Manual IOSTAT(1M) == NAME == iostat - report I/O statistics == SYNOPSIS == iostat [ option ] ... [ interval [ count ] ] == D...