The Log level determines how much information is logged for each executed Process step. The following log levels are available, from least to largest amount of logged data:

As the name suggests, only errors will be logged with this Log level setting. No step or Subprocess execution data will be logged, which will speed up Process execution and log message processing as a whole. Promoted variables are logged no matter what log level is used.

If an exception happens within the Process, then the parameters used for that Task or Subprocess will be logged along with the exception. The result of steps which are set to promote result are also logged, as always.

Note that if you have promoted results in Subprocesses, or handle any exceptions without rethrowing them, the Subprocess instances themselves are not logged under the Only Errors Log level, whereas the steps are. This may lead to redundant logging of data that you cannot actually view. The data will eventually be cleared, but for maximum performance, you should not promote results of Subprocesses under the Only Errors log level.

The Default Log level logs results for each step executed in a graph, with the exception of Foreach Elements. Parameters for Tasks and Subprocesses are not logged by default, nor are the variable references used in expressions for Condition branches or While loops. In case parameters or results are very large (over 10 000 characters), the logged value will be truncated.
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Only the first 100 Elements are logged in arrays, also those used as parameters in Foreach loops. Each Element can have up to 10 000 characters, until the logged value will be truncated.

If a Process step fails, parameters for that step are logged.

Sometimes you need to know everything that happens within a Process - this is especially useful when developing a new Process. With the Everything Log level every parameter and each result is logged. For conditional expressions, referenced variable values are also logged. Log level Everything will log the full values, and not truncate large result or parameter sets, as the Default Log level would do.

The next article is Introduction to Log process parameters and return value

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