Tandem Capacity Model (TCM) Manual

WA Model TCM Parameters Screen
You can use the Workload Apportionment model TCM Parameters screen to change the default
process priorities and to set the Disk Process Apportionment Factors, History File Name, and Default
Process Priorities parameters for the WA model. Figure 39 (page 115) shows a sample TCM
Parameters screen for a Workload Apportionment model.
Figure 39 Workload Apportionment Model TCM Parameters Screen
Significant Rows
1. Disk Process Apportionment Factors—Modifiable by the TCM administrator
Disk Process Apportionment Factors are the factors used to apportion the CPU seconds
consumed by the disk process based on cache hits and misses. These factors are used when
you select Workload Apportionment from the Update menu. The default settings assume that
a cache miss requires twice the CPU time as a cache hit.
2. History File Name—Directly modifiable
History File Name is the file name of the Capacity History database. The default file name
consists of the first eight characters of the application name with an .HST extension, but you
can overwrite it.
3. Query Transaction OLTP-> Batch Response Time CPU Pathlength Threshold—Directly modifiable
Query Transaction OLTP-> Batch Response Time CPU Pathlength Threshold specifies the point
at which a query transaction is considered either an OLTP or a batch transaction. The default
setting is 2 seconds. Small demand queries taking less than two seconds are considered OLTP
transactions. Large demand queries taking longer than two seconds are considered batch
transactions. Any TCM user can modify this parameter.
WA Model TCM Parameters Screen 115