Logging

The Error Log operation of the SVAdm tool allows you to record execution of the product on the server. System logging can be useful in tracking down performance and system errors. Log files, by default, will be placed in the \Program Files\Winshuttle Workflow\logs directory.

The most common logging level is Info. Other logging levels are Debug, Warn, and Error. In the case of exceptions, if the logging level is anything except Error, then that exception was expected by the system, and can be safely ignored. If the logging level is Error, then the exception was not expected, which indicates that the condition was a true exception in the system.

Note: Some exceptions are normal and expected during the everyday running of Workflow. To determine if an exception is expected or unexpected, look at the logging level near the beginning of the logging line.

There are three types of logging:

• Core — the default type, which logs the internal workings of the product that runs in the context of SharePoint.
• Timer — logs timer marks within the core product, which can be useful if there are performance problems.
• SVService — logs SVService.

Workflow supports four levels of logging:

• Error — typically logged whenever a serious exception is thrown. This level of logging affects performance the least.
• Warn — this level is used whenever something is detected that is wrong, but is not necessarily fatal. If the system encounters some condition that was not expected, but that was not serious enough to throw an exception, a description will be written to the log at a logging level of Warn. Errors are also included in this level.
• Info — general tracing messages throughout the code. No string composition is done at this level, so no variable data is written at this level. Errors and Warnings are also included in this level.
• Debug — the most detailed logging level. Includes variable data, so string composition is done extensively, which can trigger more frequent garbage collections, etc. Errors, Warnings, and Informational messages are also included in this level. This level of logging has the greatest impact on performance.

The impact of logging on performance corresponds to the amount of data written to the log file and how the strings are composed. In most circumstances, using Error or Warn level logging will have no noticeable impact on performance because under normal circumstances very little would be written to the log at these levels. The Info and Debug levels of logging will have a greater impact on performance.

Searching through Logs

To easily search for any logging level with a text editor, search for a "|" immediately followed by the logging level name. For example, if you are examining a log to try to find where an error occurred, you should search for "|Error". If that yields nothing, search for "|Warn," remembering that exceptions caught and logged under the Warn level were expected, and probably do not indicate a source of the error.