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3rd chunk of `iostat.man`
d10d47da5b0bb9a1c39fcdf1ccbac2dbc5674ed1b2bc69a40000000100000fa0
   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)
                     The number of sectors (kilobytes, megabytes) written to the device per second.

              dsec/s (dkB/s, dMB/s)
                     The number of sectors (kilobytes, megabytes) discarded for the device per second.

              rqm/s  The number of I/O requests merged per second that were queued to the device.

              rrqm/s The number of read requests merged per second that were queued to the device.

              wrqm/s The number of write requests merged per second that were queued to the device.

              drqm/s The number of discard requests merged per second that were queued to the device.

              %rrqm  The percentage of read requests merged together before being sent to the device.

              %wrqm  The percentage of write requests merged together before being sent to the device.

              %drqm  The percentage of discard requests merged together before being sent to the device.

              areq-sz
                     The average size (in kilobytes) of the I/O requests that were issued to the device.
                     Note: In previous versions, this field was known as avgrq-sz and was expressed in sectors.

              rareq-sz
                     The average size (in kilobytes) of the read requests that were issued to the device.

              wareq-sz
                     The average size (in kilobytes) of the write requests that were issued to the device.

              dareq-sz
                     The average size (in kilobytes) of the discard requests that were issued to the device.

              await  The average time (in milliseconds) for I/O requests issued to the device to be served. This includes the time spent by the requests in queue and the time spent servicing them.

              r_await
                     The average time (in milliseconds) for read requests issued to the device to be served. This includes the time spent by the requests in queue and the time spent servicing them.

              w_await
                     The average time (in milliseconds) for write requests issued to the device to be served. This includes the time spent by the requests in queue and the time spent servicing them.

              d_await
                     The average time (in milliseconds) for discard requests issued to the device to be served. This includes the time spent by the requests in queue and the time spent servicing them.

              f_await
                     The average time (in milliseconds) for flush requests issued to the device to be served.  The block layer combines flush requests and executes at most one at a time.  Thus flush operations could be twice
                     as long: Wait for current flush request, then execute it, then wait for the next one.

              aqu-sz The average queue length of the requests that were issued to the device.
                     Note: In previous versions, this field was known as avgqu-sz.
Title: iostat Device Utilization Report: Continued Metrics
Summary
This section continues the description of the Device Utilization Report from `iostat`, detailing various metrics for each device. It includes: read/write/discard requests merged per second; percentages of merged read/write/discard requests; average size of I/O requests (total, read, write, discard); average time for I/O requests to be served (total, read, write, discard, flush); and average queue length of requests.