Tandem Capacity Model (TCM) Manual

1. Check that the CPU and disk apportionments per transaction are in line with what you would
expect. For example, you need to validate your apportionment method if your results show 2
seconds of CPU time for a transaction that you expect uses 500 milliseconds of CPU time.
2. From the Find menu, select CPU, Disk Read, or Disk Write, under the Work Apportionment
option, to view each apportionment in detail. Figure 18 (page 80) shows a sample CPU
Workload Apportionment screen.
Figure 18 CPU Workload Apportionment Screen
3. Select Find > Workload Summary to get a summary of transaction costs in terms of time.
Figure 19 (page 80) shows a sample Workload Summary screen.
Figure 19 Workload Summary Screen
Updating the Capacity History Database
Once you have created a WA model, update the Capacity History database so you can track
your apportionment methods and samples.
To update the Capacity History database, select History > Update History.
Figure 20 (page 81), Capacity History Screen shows a sample Capacity History screen after it
was updated with the default apportionment tables created for the EXAMPLE1 performance sample.
The Mix column shows the percentage of transactions in the sample. This information is useful for
validation.
80 Creating a WA Model