ASP.NET Core Performant logging

One of the hidden features of ASP.NET Core is the support for LoggerMessage.

From the documentation:

LoggerMessage features create cacheable delegates that require fewer object allocations and reduced computational overhead compared to logger extension methods, such as LogInformation, LogDebug, and LogError. For high-performance logging scenarios, use the LoggerMessage pattern.

LoggerMessage provides the following performance advantages over Logger extension methods:

• Logger extension methods require "boxing" (converting) value types, such as int, into object. The LoggerMessage pattern avoids boxing by using static Action fields and extension methods with strongly-typed parameters.
• Logger extension methods must parse the message template (named format string) every time a log message is written. LoggerMessage only requires parsing a template once when the message is defined.

The best way to use it is through some extension methods on the ILogger interface:

• Create a static LoggerExtensions class
• Add a static constructor and use the Define(LogLevel, EventId, String) method to create an Action delegate for logging a message. For the Action, specify:
• The log level.
• A unique event identifier (EventId) with the name of the static extension method.
• The message template (named format string).
• Store the created Action delegate in a private static field
• Create an extension method that invokes the delegate