Model Forecasting

The model creation and validation processes presented in the previous chapter, provide an accurate snapshot of your host system. The procedures in this chapter allow you to add the dimension of time to your model to accurately predict the future performance of your host system.

The procedures in this chapter assume:

Forecast Capacity Planner is installed and running on your PC.

The data collection process on the host system is complete and the collection file (*.col) is transferred to your PC.

The loading and validation process is complete and you have a validated model (*.mdl) on your PC.

Configuring the Forecast Model

Before graphing a performance projection from your validated model, decide what you hope to achieve with your projection. For example:

What do you want your performance projection graph to show?

How fast do you expect utilization to increase on your system in the next quarter or the next year?

Do you expect utilization to increase uniformly on the system, or do you expect some workloads to grow faster?

How far into the future do you want to look?

How do you want the information presented?

Do you want to group all workloads and resources as a single line?

Do you want to graph some workloads or resources separately?

The answers to these questions and other questions are figured into your performance projection. Use the Forecast Options to set the values on which your projection is based.

Setting Forecast Options

To set forecast options:

On the Forecast menu, click Forecast Options.

From the Options tab in the Forecast Options dialog box (Figure 10.1), enter or select new options as described in Table 10.1.

Figure 10.1 Forecast Options dialog box: Options tab

Click OK to apply the change(s) and return to the Main Program window, or click the Rates tab to change the forecast growth rates.

Table 10.1 Forecast options

Forecast Option	Instructions to Set Forecast Options
Start month	Verify the starting month for your performance projection.
Periods	Enter the number of periods (months, quarters, or years) to be shown on the graph.
Growth type	Select the global growth type: Select Workload to apply the growth type specified in your validated model for each workload to your forecast graph. Select Linear to apply the linear growth type for all workloads, regardless of the growth type specified for that workload in your validated model. Select Compound to apply the compound growth type for all workloads, regardless of the growth type specified for that workload in your validated model. Select Tiered to apply the tiered growth type for all workloads, regardless of the growth type specified for the workloads in your validated model.
Period type	Select the period type: months, quarters, or years.
Workloads	Select individual workloads to chart during the performance projection. Selecting All Workloads reports the total of all unselected workloads as a single line in the graph.
Start year	Verify the starting year for your performance projection.
Adjusts Results	Select the Adjusts Results check box to adjust forecast results to match the observed system values.
Graph type	Select the graph type: Resp Time Throughput CPU Util Disk I/O Disk Util
Growth option	Select the global growth option: Select Workload to apply the growth rate specified in the Edit window of the individual workload groups. Select Override to apply the growth rate in the Forecast Options window Rates tab to the model globally. This setting will override the individual settings. Select Add to apply the sum of the global growth rate and the individual workload growth rate in your validated model. Select Rep Zero to apply the global growth rate only if the individual rate is zero.
CPUs	Select the CPU models to chart in the performance projection.
Disks (only visible when Graph Type is set to a disk chart)	Select individual disks to chart in the performance projection. Selecting All Disks reports the total of all unselected disks as a single line in the graph.

Setting Forecast Growth Rates

To set forecast growth rates:

On the Forecast menu, click Forecast Options.

In the Forecast Options dialog box, click the Rates tab (Figure 10.2).

Figure 10.2 Forecast Options dialog box: Rates tab

Enter or select new options as described in Table 10.2.

Click OK to apply the change(s) and return to the Main Program window.

Table 10.2 Rates options

Rates Option	Instructions to Set Rates Options
Tiered rate	In the Options tab, ensure Tiered is selected as the Growth type option. In the Rates tab, enter the Tiered rate (the percentage of the growth rate that will remain after it is applied).
Growth rate	Enter the global growth rate for your performance projection.
Apply growth period	Select Month, Quarter, or Year. The growth period determines how frequently the growth rate is applied in the performance projection.

Based on the information in your validated model and the options set in the Forecast Options dialog box, Forecast Capacity Planner creates a dynamic model of your system. You can view, print, or export that model in either a graphic format or a report format.

Aging the Forecast Model

The aging function of Forecast Capacity Planner offers a quick and easy way to generate forecasting information about your model. The aging function enables you to fast forward to a future date and view the effects of workload growth rates on the model. The aged model is based on the growth rates assigned to your workloads in the validated model. (See "Editing a Workload Group" for more information about changing workload growth rates.)

To age the model:

On the Forecast menu, click Age Model.

In the Age Model dialog box, enter the number of months to age the model.

Figure 10.3 Age Model dialog box

Click OK to apply the change.

To return to a non-aged model (the original model), click Undo from the Edit menu. This can be done even if you saved the aged model.

Creating Forecast Reports

Use the Report Fonts and Report Options commands to change the appearance of your printed reports.

Setting Report Fonts

On the Options menu, click Report Fonts.

In the Font dialog box, specify the following:

Font

Font style

Size

Sample

Script

Click OK to save the change(s) and return to the Main Program menu.

Setting Report Options

On the Options menu, click Report Options.

From the Page Setup tab in the Report Options dialog box (Figure 10.4), enter or select new options as described in Figure 10.4.

In the Measure units field, select Inches or Centimeters. This field determines the unit of measurement for the rest of the options in this tab:

Field minimum size

Field maximum size

Distance between fields

Distance between rows (row height)

Figure 10.4 Report Options dialog box: Page Setup tab

Click OK to apply the change(s) and return to the Main Program window, or click the Margins Setup tab to change the report margins.

In the Report Options dialog box, click the Margins Setup tab (Figure 10.5).

Figure 10.5 Report Options dialog box: Margins Setup tab

Enter or select new options as described in Figure 10.5.

In the Measure units field, select Inches or Centimeters. This field determines the unit of measurement for the rest of the options in this tab:

Left margin

Top margin

Bottom margin

Distance between rows (row height)

Click OK to apply the change(s) and return to the Main Program window.

Printing Forecast Reports

Performance Gallery Gold uses a standard Windows-based Print menu.

Setting Print Parameters

To specify the parameters for your print request, such as the paper size and orientation:

On the File menu, click Print Setup.

Set the print parameters.

Click OK to save the print parameters and return to the Main Program window.

Previewing Forecast Reports

To preview the print job prior to printing:

From the file manager pane in the Main Program window, select the Model icon.

On the File menu, click Print Preview.

Click Zoom In to examine the page in closer detail.

Click Zoom Out to view the entire page.

Click Next Page to view the next page.

Click Previous Page to view the previous page.

Click Two Page to view two consecutive pages, side by side.

After previewing the print job, either click Close to return to the Main Program window, or select the Print... command button to send the chart(s) to the printer.

Printing Forecast Reports

To send a forecast report to the printer:

From the file manager pane in the Main Program window, select the Model icon.

On the File menu, click Print.

From the Print submenu, click Model.

Before the report is actually sent to the printer, the Print dialog box will prompt you to check the print settings. Click OK to send the print request.

Exporting Forecast Reports

To export a forecast report to another application:

From the file manager pane in the Main Program window, select the Model icon.

On the Forecast menu, click Copy to Clipboard.

Paste the report into your document or presentation application.