A System Center Capacity Planner 2007 application model defines the performance characteristics of a specific application and its components and is stored within Capacity Planner. Capacity Planner uses these performance characteristics to simulate the performance of a deployed system. Using input that you provide and the particular application model, currently Microsoft Exchange Server, the Capacity Planner Model Wizard generates a capacity model.
Application models stored in Capacity Planner consist of the following:
- A list of transactions. A transaction
is a single instance of activity or work, as perceived by a user of
Exchange Server.
- A list of application
components. Application components are
discrete parts of an application. For example, the mailbox store is
an Exchange Server application component.
- A list of workload parameters. Workload
parameters are values that are used by a capacity model as part of
an action (for example, how large an e-mail message to send through
a network interface), part of a transaction (for example, how
frequently this transaction occurs relative to other transactions),
or part of the overall simulation (for example, how many
transactions to send). You provide the values for workload
parameters in the Model Wizard and the Model Editor.
Hardware Limitations in Capacity Planner Application Models
The hardware modeling limitations for Capacity Planner application models are described in the following table.
| Hardware | Limitation |
|---|---|
|
Memory |
Capacity Planner does not actively model memory requirements. Memory requirement recommendations in Capacity Planner are based on best-practice advice for each application model. |
|
Disks |
Capacity Planner requires single-disk configurations to have write caching disabled. If write caching is enabled on single disks in a test environment, simulation results that are obtained from Capacity Planner do not correspond to the actual test results. |
|
CPUs |
As many as eight processors per server and two cores (dual core) per processor can be modeled. |
|
Switches and routers |
Performance is not modeled, although visual indicators for these items are included in the capacity model, appearing in the Model Editor. |
|
Firewalls |
Firewalls are not modeled. Capacity Planner models only required infrastructure that affects performance. |
|
Client computers |
Overall performance of client computers is not modeled, although network traffic to and from clients is modeled. |
|
LANs |
Only packet-switched Ethernet networks are modeled. All network connections are full duplex. |