Device Path Exerciser Logs

Device Path Exerciser creates and maintains a set of detailed log files. Some of the logs are designed to help the user identify the test that a driver failed. Others are maintained by Device Path Exerciser for its own use.

All log files are stored in the current directory. You cannot specify different log file names or locations.

You can adjust the level of detail in the user logs to meet your needs. Increase the detail to produce detailed records of each test event or reduce the detail to make the tests run faster.

Device Path Exerciser uses write-through logging, a method that writes text immediately to disk, instead of accumulating it in a buffer. This method assures that the logs provide an accurate account of the crucial final moments of a test, even when the test causes a system crash. However, the frequent disk I/O consumes enormous amounts of time and resources.

Do not increase the detail level in a log unless it is necessary. A detailed log can extend the run time of Device Path Exerciser from a few minutes to a few days.

Device Path Exerciser generates four log files.

Dc2.log

The Dc2.log file is an event log designed for the user. Depending on the logging level that you select, Device Path Exerciser can record the precise details of each test, including the exact calls sent to the device, or it can record only the start and end of each major test or test section, or only the command used to start Device Path Exerciser.

Each time that Device Path Exerciser runs, it overwrites any previous copies of Dc2.log in the current directory. To retain the file, rename it, or move it to a different location.

To configure the logging level of the Dc2.log file, use the /ltx parameters. The default value is +ltt (log all events).

Diags.log

The Diags.log file is a results log designed for the user. Depending on the logging level that you select, Device Path Exerciser can record informational messages, warnings, errors, fatal errors, or it can record nothing.

Each time that Device Path Exerciser runs, it appends the new data to the current copy of Diags.log in the current directory. Because this file can get very large, you might want to delete it periodically, especially when you complete the testing of a device or driver.

To configure the logging level of the Diags.log file, use the /ldy parameters. The default value is +ldi (log information, warnings, errors, and fatal errors).

Crashn.log

The Crashn.log file, also known as the restart log, stores a history of the tests run during previous Device Path Exerciser test sessions. This file provides data for the /c (skip tests that crashed the driver) and /r (skip tests already performed) test parameters.

Device Path Exerciser maintains only one Crashn.log file. (The n is a constant; it does not represent a version number.) Each time that Device Path Exerciser runs, it appends the new data to the current copy of Crashn.log in the current directory.

To take advantage of the test history that Device Path Exerciser maintains, this file must remain in the current directory. Do not delete, rename, or move this file until you are finished testing the driver or device. Then, delete the file so that it does not affect tests of other drivers or devices.

However, you can edit this file to adjust the restart behavior. For example, if you want Device Path Exerciser to skip all but one completed test, delete that test from the Crashn.log file.

To configure the logging level of the Crashn.log file, use the /lrz parameters. The default value is +lra (log all restart information).

Crash.log

The Crash.log file is a running list of the tests that caused the system to crash. Device Path Exerciser creates this file only when you use the /c or /r parameters to skip tests that are completed or that crashed the system.

If you use the /r parameter, which skips tests that have already run (including those that crashed the system), Device Path Exerciser appends the contents of the Crashn.log file to the Crash.log file.

If you use the /c parameter, which skips tests that crashed the system, Device Path Exerciser appends the last line of Crashn.log to Crash.log, because it assumes that the last line in the log is a record of the event that caused the system to crash. If the previous test session completed successfully, Device Path Exerciser still copies the last line, in that case, the elapsed time of the previous test session.

You cannot configure the logging level or any other feature of Crash.log.

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Build date: 9/28/2012