Tandem Capacity Model (TCM) Manual

Change Password
The Change Password option changes the TCM passwords that control access to TCM administrator
and superuser authorization levels. The default password for the TCM administrator level is “admin.”
The password for the superuser level is “super.” To enhance TCM security, modify the default
passwords. This option is available only to users with a TCM administrator or superuser authorization
level.
After you select this option, a dialog box prompts for both the existing and new (replacement)
passwords. For more information regarding TCM passwords, see “Passwords” (page 69).
Enter Excel (F4)
The Enter Excel option, available only to users with a superuser authorization level, allows you to
access the standard Excel ribbon so you can execute any Excel commands you want. You can use
non-TCM spreadsheets when you are in Excel, but be sure to close any spreadsheets that are not
part of a normal TCM session before returning to TCM.
Returning to TCM from Excel
If you enter Excel from TCM and want to return to TCM from Excel, select Enter TCM from the Excel
Home tab or press Shift-F4.
Expert Tab
The TCM Expert tab provides options to generate a Workload Apportionment Weights table,
update history with selected samples, create a default Transaction Count table, pick the best sample,
and view or modify TCM Expert parameters. This tab is available only if you selected the TCM
Expert option on the initial TCM tab.
For more information on these options, see Chapter 10: “Using TCM Expert”.
Generate Expert Apportionment Weights
The Generate Expert Apportionment Weights option generates a Workload Apportionment Weights
table and updates a History file automatically. A dialog box provides fields for you to enter the
name of the history file. If one does not exist, TCM creates it. The field labeled Apportionment
Table File enables you to select an existing Transaction Count table and provides the name for the
Apportionment Weights table that TCM Expert generates. In addition, you can add or remove the
CSV files to be used in the generation from this dialog box.
Data Splitting
TCM Expert uses the statistical concept of data splitting to give you a higher confidence level in
its results. When TCM Expert generates apportionment weights, it uses 2/3 of the CSV files selected.
TCM Expert does not use the other 1/3 of the CSV files selected but reserves those CSV files as a
test sample for consistency. When TCM Expert updates the history file, it uses all of the CSV files
selected and at that time tests all of the samples for consistency. If TCM Expert finds inconsistencies,
it reports this information in a dialog box.
If you are a TCM super user, the dialog box shows Percent of Selected CSVs used to generate. (If
you are not a TCM super user, the dialog box does not show this field.) This field shows the
percentage of CSV files out of all the selected CSV files from which TCM Expert generates the
Apportionment Weights table. The default is 67 percent. If you have too few samples to make an
accurate Apportionment Weights table, you might want to increase this percentage. By increasing
this percentage, you have a better chance of getting an accurate Apportionment Weights table,
but you reduce the confidence level of the results.
132 Workload Apportionment Model