Tandem Capacity Model (TCM) Manual

by selecting Calculate Now from the Options tab (if no table exists). For categories other than
server, the default table assumes that category demand is spread evenly (on a per-transaction
basis) across all transactions. For server categories whose names match a transaction name,
the default table assumes that category demand is 1 for the transaction with the matching
name and 0 for all others.
In some cases, however, a transaction might consume more of a certain resource per transaction
than another transaction does. For example, in a Pathway system, the requesters for transactions
Txn 1 and Txn 2 might use the same TCP, but Txn 1 might be a heavy requester and Txn 2 a
light requester. In this case, the TCM administrator would modify the relative weights in the
default Apportionment Weights table to reflect the difference.
Transaction Count Table
The Transaction Count table is used by the TCM administrator to specify how the WA model should
compute the number of transactions measured by Measure during the time period of the sample
window on the NonStop host system. TCM calculates transaction counts from the entries in this
table, the number of messages received, sent or both by process categories into transaction counts.
Figure 41 (page 118) shows a sample Transaction Count Table. For more information, see “Example
of a Transaction Count Table” (page 72).
Figure 41 Transaction Count Table
Significant Columns
1. Cat Name—Not directly modifiable
Cat Name is the category name of all process categories as they appear on the Category
Demand report. The table is used to indicate how the CPU and disk seconds consumed by
these categories are to be allocated to each transaction.
2. Type—Modifiable by the TCM administrator
The type of process category, as defined in MeasTCM on the NonStop host system. The
category type consists of one of the following characters:
Server processS
Requester processR
Disk process (including all nonaudited disk processes)D
118 Workload Apportionment Model