Tandem Capacity Model (TCM) Manual

1. From the “TCM Initial Menu” (page 66), select Work with an Existing WA Model or Work
with an Existing Performance Model and then click OK.
The Open PM Model or Open WA Model dialog box appears.
2. If you want to view all possible Workload Apportionment models, type *.SWA in the Model
to Open field. Type *.SPM to see all possible Performance models.
3. Select a file from the list or enter the file name you want to open, including its .SWA or .SPM
extension.
4. Click OK. TCM loads the model file (rather than the Excel workspace file).
Performance Model Options
After you have worked with the WA model and created an apportionment method that is reasonable,
you can use the Performance model to answer what-if questions about system capacity and the
performance of your application. For more information on determining whether an apportionment
method is reasonable, see “Checking an Apportionment Method” (page 82).
Demonstrate Option
When you choose the Demonstrate option, TCM displays a Performance model that you can use
for practice. You can make changes in the sample model, but you cannot save the changes.
Create a New Performance Model Option
When you select Create a New Performance Model, you are prompted to select the WA model
to load from a list of available WA models.
Work with an Existing Performance Model Option
When you select Work with Existing Performance Model, you can review or modify an existing
Performance model. You can also use an existing Performance model to add new baseline data
if you want to retain your what-if conditions but change the baseline data.
TCM Expert Option
TCM Expert provides a way to do capacity planning when you have limited knowledge of the
application design or architecture. To access the Expert features of TCM, click the TCM Expert
button. When you click this button, TCM adds the TCM Expert tab to the WA model tabs. For a
description of TCM Expert, see Chapter 10: “Using TCM Expert”.
Security
TCM has security features to prevent you from unintentionally corrupting algorithms or sample
data. Password-protected user authorization levels are built into the product to:
• Restrict access to commands that are particularly crucial in the modeling process.
• Restrict modification of specific fields in TCM models. Only highlighted fields in TCM can be
directly modified. Most of the fields are protected and cannot be changed. Authorization
levels are used to control the number of highlighted fields in the model. User modifiable and
nonmodifiable fields are a different color.
User Authorization Levels
TCM has three authorization levels associated with the three types of TCM users.
Capacity Planner
The capacity planner is the most restricted authorization level in TCM. It is not password-protected.
It provides access only to the basic TCM commands, enabling you to define and analyze alternative
capacity management approaches using existing custom models.
68 Getting Started With TCM