SMF Extensions › Features and Benefits › Chargeback Algorithms Used › BATCH Charges

BATCH Charges

1. The Total Charge is calculated as:

   Total Charge in Dollars = (Sum of the step charges x
                             Priority Factor x
                             Job Class Factor)
   Step Charge in Dollars =  (Processor Charge + I/O Charge)
   

   The only adjustments applied at the job level are Priority and Job Class factoring. The Priority and Job Class tables contain these factors.

2. The Processor Charge is computed on a per step basis as follows:

   Processor Charge = Processor Time x Adjusted Rate

3. The time factor in the Rate Table enables a user to weigh or delete the various recorded times when calculating the processor time.

   The Processor Time is calculated as follows:

   Processor Time = ((Elapsed Time   x Elapsed-Time-Factor) +
                     (Total CPU Time x Total-CPU-Factor)    +
                     (SRB CPU Time   x SRB-CPU-Factor)      +
                     (TCB CPU Time   x TCB-CPU-Factor))
   

   This algorithm permits a charge which includes all four times at 100%. Obviously, this results in overcharging. Though the algorithm permits this overcharging, the recommended approach is to charge for Total CPU alone at 100%. The other factors should be set to zero. Total CPU is the most repeatable and uniform measure of CPU utilization for a given processor and, therefore, is likely to be the most equitable variable to use.

4. The Adjusted Rate allows for charging to be a function of memory utilization as well as CPU time. The Core Factor in the Rate Table lets you charge for the utilization of memory as a function of time (duration of use). This dollar amount is charged per 1K block of core. The Core Indicator (in the Rate Table) selects either Core Used or Core Allocated. In the formula below, this choice of memory measured is shown simply as the word CORE:

   Adjusted Rate = Basic-Processor-Rate +
                   (Core x Core-Factor)
   

5. The I/O Charge is calculated by applying the appropriate factor to EXCP counts (if available) for each device, and adding the individual costs. If a device falls in an address range specified in the CONFIG Table or if the GNRC(YES) option is used, then the corresponding device factor from the Rate table is applied.

   The I/O Charge is calculated as follows:

   I/O Charge = ((Reader  I/O Count x Reader-I/O-factor)  +
                 (Printer I/O Count x Printer-I/O-factor) +
                 (Punch I/O Count   x Punch-I/O-factor)   +
                 (Tape I/O Count    x Tape-I/O-factor)    +
                 (Disk I/O Count    x Disk-I/O-factor)    +
                 (Other I/O Count   x Other-I/O-factor))  / 1000
   

The result of the computations is an estimated step charge which is summed to produce the total estimated job charge. The charge is estimated and does not balance exactly to a CA JARS batch run due to a number of factors. Rounding is one factor. Another factor is that SYSOUT charges are not included in this estimated charge. SYSOUT charges are based on the SMF Type 6 record which is usually written sometime after the job terminates and is therefore unavailable for cost calculation in SMF/E.