Interpreting a Performance Results File

The WCAT performance results file displays the data collected from the performance counters on the server. The data is displayed in a comma-separated, variable-length format, so the file can be used as input for a data processing or spreadsheet application. The file cannot be used as input for Performance Monitor, however; Performance Monitor cannot display charts or reports from WCAT output files.

Tip

Look at the sample performance results file included with WCAT for reference while you are reading this section. The sample file, 1ktest01.prf, appears on the Supplement 1 CD-ROM. You can use any text editor or word processor to view the 1ktest01.prf file. You can also load the file into any data processing program or spreadsheet for viewing or analysis.

The performance results file is made up of three sections:

· A file header

· Column headings

· A table of performance data

File Header

The performance results file begins with a header identifying which test run the given output relates to and what information is included.

For example:

The fields in the header are as follows:

· File lists the path and filename of the performance counter input file.

· NumCounters displays the number of counters requested in the performance counter input file.

· MachineName displays the name of the server computer whose performance counters were monitored.

· Start Time displays the time WCAT started on the controller.

WCAT begins monitoring performance counters when the warmup period ends. The Start Time field does not display the time monitoring began, but you can determine the beginning of monitoring. At the conclusion of the warmup period WCAT displays the following message at the command prompt:

This message signals the beginning of monitoring.

Column Headings

After the header, the next section of the file is a comma-separated stream of column headings for the table that follows. The column headings appear in the same order as the columns appear in the table. Use your spreadsheet program to associate each column heading with the column it names.

The following is an example of column headings:

Performance Counter Table

The last section of the performance results file is a table displaying the data collected from the server performance counters. Each column of the table represents a performance counter, except for the first column, TimeSlice. The TimeSlice column indicates how often the Performance Monitor counters were monitored during the test, in seconds. WCAT tries to monitor the counters every 10 seconds, but attempts might be delayed if the processor is busy. Each row of the table represents one observation.

Each entry in the table represents the value of one counter when it was observed. The values are displayed in the units native to the counter. For example, in the table following the 9 in the first row of the second column represents 9 percent processor use, while the 9 in the second row of the sixth column represents nine page faults per second.

To interpret the table, associate each column with its column heading. The columns appear in the same order as the column headings.

For more information on interpreting the values of Performance Monitor counters, see the Help file Counters.hlp; Windows NT Workstation Resource Kit, Part 3, “Optimizing Windows NT Workstation”; and Supplement 1, Part II, “Optimizing IIS Server Performance.”