topio(8)                            CLIX                            topio(8)



  NAME

    topio - Runs CRM utility for monitoring I/O activity

  SYNOPSIS

    /usr/ip32/crm/topio [-U boot_image] [-I interval] [-S snap_file] [-i
    input_file] [-o output_file]

  FLAGS

    -U boot_image   Lists the file specification of the CLIX image which was
                    booted.  This flag is required only if the boot image has
                    been moved since the system was booted.  (The default boot
                    image used is set on the Operating System Parameters menu
                    of the workstation Utility Pages; usually, the image is
                    the /unix file.  However, if the user moves the boot image
                    to a different directory, the -U flag must be used to tell
                    the CRM utilities where to find the boot image.)

    -I interval     Specifies how frequently the monitor samples and displays
                    information.  The interval is specified in seconds.  The
                    default interval is 2 seconds.

    -S snap_file    Specifies a name for the snapshot file.  (The default
                    filename is /tmp/CRM.snapshot.)

    -i input_file   Reads the data from input_file every interval seconds.
                    The input_file must have been created as an output_file
                    using the -o flag.  A hyphen (-) for input_file reads
                    input from stdin.

    -o output_file  Directs output to output_file.  A hyphen (-) for
                    output_file directs output to stdout.

  DESCRIPTION

    The topio command monitors the I/O activity on the system and displays
    which processes are performing the activity.

    A brief explanation of the topio fields follows.  A similar list can be
    accessed online by typing ? while the monitor is running.

    b_read, b_wrt   Displays the number of reads (b_read) and writes (b_wrt)
                    to the block-oriented device (the disk).

    l_read, l_wrt   Displays the number of data accesses (by a program) to the
                    system buffer cache.

    cache           Displays the percent of I/O that is satisfied by the
                    buffer cache (rather than by the block-oriented device, or



  2/94 - Intergraph Corporation                                              1

  topio(8)                            CLIX                            topio(8)



                    disk).  This value is derived from the difference between
                    the b_read and l_read values, and the difference between
                    the b_wrt and l_wrt values.

    phread, phwrt   Displays the number of physical reads and writes to the
                    raw disk.

    sysrd, syswrt   Displays the number of system calls to the read and write
                    functions.

    rdch, wrtch     Displays the total number of bytes (characters) that are
                    transferred by all read and write calls from a program
                    regardless of where the data came from (cache, disk, or
                    memory).

    device          Displays the Small Computer Systems Interface (SCSI)
                    devices involved in I/O on the system.

    ops             Displays the number of I/O operations that occurred on the
                    corresponding SCSI bus.

    busy            Displays the percentage of time that the SCSI device was
                    busy with I/O operations (versus how much time spent
                    idle).

    bcnt            Displays a count of disk blocks that were read from and
                    written to the device.

    avque           Displays the average number of times that I/O had to wait
                    because the SCSI device was busy servicing other I/O
                    requests.

    currque         Displays the current I/O queue depth (how many I/O
                    requests are in the queue to be serviced).

    ioch            Displays the number of characters transferred by the
                    corresponding process.

    To take a snapshot of the statistics, type S (press <Shift> <S> ).  The
    statistics shown at that instant are saved to the file /tmp/CRM.snapshot,
    or to the file specified with the -S flag.

  EXAMPLES

    The following example samples the I/O activity every five seconds.

    /usr/ip32/crm/topio -I 5


  FILES




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  topio(8)                            CLIX                            topio(8)



    /dev/kmem   Allows topio access to kernel virtual memory space.

    /dev/mem    Allows topio access to kernel physical memory space.

    /unix       The default CLIX image.  The topio command looks up offsets
                into the kernel using symbols from boot_image.

    /tmp/CRM.snapshot
                The default filename of a snapshot.

  NOTES

    Read permission is required to access some files used by this command.  If
    the user is denied permission to access the required files, the superuser
    privileges are required to run this command.

  CAUTIONS

    Sending raw data to a file can create a very large file, which can result
    in unexpected ``disk full'' messages.

  DIAGNOSTICS

    The diagnostic messages are designed to be self-explanatory.

  EXIT VALUES

    The exit values are not valid.

  RELATED INFORMATION

    Commands:  crm(1)






















  2/94 - Intergraph Corporation                                              3