The .NET Exception rate score rule detects excessive exception rates that can have a negative impact on your application's performance.

A high rate of .NET exceptions can impact your performance in two important ways:

1. Exception processing/handling is an expensive task, and can consume a significant amount of CPU cycles that can otherwise be used for the application's workload.

2. Exceptions often cause aborted processing, causing wasted work, additional cleanup, and additional resources such as database connections, open files, and so on.

Diagnostics
When LeanSentry diagnoses .NET Exceptions, it will identify the most prevalent exceptions contributing to the high exception rate.

You can then review these exceptions, their messages, and the associated stack trace, to identify which portions of your code are responsible.



Improving this score
To improve the score, identify the exceptions contributing to a high exception rate, and either:

1. If the exception is due to an error, attempt to fix this error.

2. If the exception is expected, change your code to signal the expected condition without raising an exception.

For more on this best practice, please see this link.