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2nd chunk of `iostat.man`
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 which the system had an outstanding disk I/O request.

              %steal Show the percentage of time spent in involuntary wait by the virtual CPU or CPUs while the hypervisor was servicing another virtual processor.

              %idle  Show the percentage of time that the CPU or CPUs were idle and the system did not have an outstanding disk I/O request.

       Device Utilization Report
              The second report generated by the iostat command is the Device Utilization Report.  The device report provides statistics on a per physical device or partition basis. Block devices  and  partitions  for  which
              statistics  are to be displayed may be entered on the command line.  If no device nor partition is entered, then statistics are displayed for every device used by the system, and providing that the kernel main‐
              tains statistics for it.  If the ALL keyword is given on the command line, then statistics are displayed for every device defined by the system, including those that have never been used.   Transfer  rates  are
              shown  in  1K blocks by default, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used.  The report may show the following fields, depending on the flags used (e.g.  -x,
              -s and -k or -m):

              Device:
                     This column gives the device (or partition) name as listed in the /dev directory.

              tps    Indicate the number of transfers per second that were issued to the device. A transfer is an I/O request to the device. Multiple logical requests can be combined into a single I/O request to the  device.
                     A transfer is of indeterminate size.

              Blk_read/s (kB_read/s, MB_read/s)
                     Indicate the amount of data read from the device expressed in a number of blocks (kilobytes, megabytes) per second. Blocks are equivalent to sectors and therefore have a size of 512 bytes.

              Blk_wrtn/s (kB_wrtn/s, MB_wrtn/s)
                     Indicate the amount of data written to the device expressed in a number of blocks (kilobytes, megabytes) per second.

              Blk_dscd/s (kB_dscd/s, MB_dscd/s)
                     Indicate the amount of data discarded for the device expressed in a number of blocks (kilobytes, megabytes) per second.

              Blk_w+d/s (kB_w+d/s, MB_w+d/s)
                     Indicate the amount of data written to or discarded for the device expressed in a number of blocks (kilobytes, megabytes) per second.

              Blk_read (kB_read, MB_read)
                     The total number of blocks (kilobytes, megabytes) read.

              Blk_wrtn (kB_wrtn, MB_wrtn)
                     The total number of blocks (kilobytes, megabytes) written.

              Blk_dscd (kB_dscd, MB_dscd)
                     The total number of blocks (kilobytes, megabytes) discarded.

              Blk_w+d (kB_w+d, MB_w+d)
                     The total number of blocks (kilobytes, megabytes) written or discarded.

              r/s    The number (after merges) of read requests completed per second for the device.

              w/s    The number (after merges) of write requests completed per second for the device.

              d/s    The number (after merges) of discard requests completed per second for the device.

              f/s    The  number (after merges) of flush requests completed per second for the device.  This counts flush requests executed by disks. Flush requests are not tracked for partitions.  Before being merged, flush
                     operations are counted as writes.

              sec/s (kB/s, MB/s)
                     The number of sectors (kilobytes, megabytes) read from, written to or discarded for the device per second.

              rsec/s (rkB/s, rMB/s)
                     The number of sectors (kilobytes, megabytes) read from the device per second.

              wsec/s (wkB/s, wMB/s)
Title: iostat: Device Utilization Report Details
Summary
This section describes the Device Utilization Report generated by `iostat`. It details the statistics provided for each physical device or partition, including device name, transfers per second (tps), data read/written/discarded per second and total, read/write/discard requests per second, flush requests per second, and sectors read/written/discarded per second. Units can be displayed in blocks, kilobytes, or megabytes. The report shows statistics for all devices unless specific devices or partitions are specified, or the ALL keyword is used.