7. PARAMETERS › 7.2 VTS Component Parameters › 7.2.3 VTS Component Unit Level Parameters › 7.2.3.1 VTS Processing Options (VTSOPS) › 7.2.3.1.4 RTDMOUNTTIME and VTVMOUNTTIME Statements

7.2.3.1.4 RTDMOUNTTIME and VTVMOUNTTIME Statements

The RTDMOUNTTIME and VTVMOUNTTIME statements are optional and
only apply to units processing StorageTek VSM data.  These
statements define seven mount time threshold limits that are
used for real tape (RTDMOUNTTIME) and virtual tape
(VTVMOUNTTIME) mount time distribution calculations.

RTDMOUNTTIME Statement
----------------------
The RTDMOUNTTIME statement format is:

RTDMOUNTTIME limit1 limit2 limit3 limit4 limit5 limit6 limit7

where:

limit1-limit7 = Each mount time threshold limit is defined in
                seconds.  It can be one to four digits, with
                a maximum value of 3600.  Subsecond mount
                time limits are coded in the form .nnn,
                although subsecond mount times do not
                generally apply to real tape drives.  The
                limits can be separated by one or more
                blanks.

Default RTDMOUNTTIME statement:

RTDMOUNTTIME 5 10 30 60 120 180 240

With the above real tape drive mount time limits, the TLM
component accumulates mount distribution counters for each
real tape drive mount, as illustrated below:

   (SVTRDSTx)                    (RMRMTM)
mount counter 1:           0 <    mount      <=   5
mount counter 2:           5 <    mount      <=  10
mount counter 3:          10 <    mount      <=  30
mount counter 4:          30 <    mount      <=  60
mount counter 5:          60 <    mount      <=  120
mount counter 6:         120 <    mount      <=  180
mount counter 7:         180 <    mount      <=  240
mount counter 8:         240 <    mount

Note that the VTS component creates an eighth counter to
capture all mount events that are greater than limit7 as
defined by the RTDMOUNTTIME statement.

VTVMOUNTTIME Statement
----------------------
The VTVMOUNTTIME statement format is:

VTVMOUNTTIME limit1 limit2 limit3 limit4 limit5 limit6 limit7

where:

limit1-limit7 = Each mount time threshold limit is defined in
                seconds.  It can be one to four digits, with
                a maximum value of 3600.  Subsecond mount
                time limits are coded in the form .nnn.  The
                limits can be separated by one or more
                blanks.

Default VTVMOUNTTIME statement:

VTVMOUNTTIME  .5 1 2 5 30 60 120

With the above virtual tape drive mount time limits, the VTS
component accumulates mount distribution counters for each
virtual mount, as illustrated below:

   (SVTVDSTx)                    (VMRMTM)
mount counter 1:           0 <    mount      <=   0.50
mount counter 2:        0.50 <    mount      <=   1
mount counter 3:        1    <    mount      <=   5
mount counter 4:        5    <    mount      <=  10
mount counter 5:       10    <    mount      <=  30
mount counter 6:       30    <    mount      <=  60
mount counter 7:       60    <    mount      <= 120
mount counter 8:      120    <    mount

Note that the VTS component creates an eighth counter to
capture all mount events that are greater than limit7 as
defined by the VTVMOUNTTIME statement.

Tracking mount time distributions can be very useful.  The
majority of both real and virtual tape mount times tend to be
clustered in one to three buckets that represent normal
performance.  If the count of mounts in the higher buckets is
greater during certain hours, there may be an opportunity for
workload shifting to alleviate resource contention.

Shifting of the general distribution of mount times towards
the higher buckets may signify that the general workload has
exceeded the capacity of the existing virtual tape systems.