Enterprise Library Logging vs log4net

image I did a presentation today to the Intergen development team on the Microsoft Enterprise Library. As someone who doesn't have much experience with giving presentations I thought it went really well. I've had a lot of positive feedback from co-workers which is nice as I was sure it was going to be a disaster. (Interesting note: During one of my interviews for Intergen, in a moment of foolishness, I gave public speaking as the answer to "What is your biggest weakness?". Just as a reference to all future potential employers: my real biggest weakness is that I just work too gosh darn hard.)

One feature of my EntLib presentation that I thought was worthwhile sharing was a comparison of the Enterprise Library Logging Block verse log4net. All the examples I found on the net comparing the two were out of date. They often compared log4net with the logging in EntLib 1.1, which is quite different from EntLib 2.0 & 3.0.

Here are what I believe are the strengths of each:

Enterprise Library Logging Application Block

  • More actively developed - The recently released Enterprise Library 3.0 contained a number of new features for logging, including WCF support. The last release for log4net on the other hand was over a year ago.
  • Takes advantage of and supports newer technologies - The 3.0 release included support for WCF.
  • Integrates with other application blocks - The Policy Injection Block and Exception Handling Block both include logging handlers to automatically invoke the Logging Application Block.
  • Very extensible - Pretty much all aspects of the Logging Block can be extended and customized. You can create your own TraceListeners, Filters and Formaters quite easily.
  • Configuration tool - Enterprise Library comes with a great tool for creating and modifying its configuration sections. This takes away a lot of the pain and guess work of configuring the EntLib application blocks.


  • Works with .NET 1.0 & 1.1 - The much improved logging of EntLib 2.0 and above is only available if your application is running on .NET 2.0 or greater. log4net however works on all versions of .NET.
  • Simpler install - When using the Enterprise Library there are some services you really should install. This is as simple as running a bat file included with EntLib but it does complicate your deployment process.
  • Slightly faster - log4net was significantly quicker than EntLib 1.1 logging. EntLib 2.0 onwards has improved its performance but log4net remains slightly faster. A benchmark I found while researching my presentation had EntLib taking approximately 5-6 seconds to log 100,000 entries while log4net took about 3 seconds. Does the speed difference matter? Probably not. However log4net net does support...
  • Appender Buffering - Buffering support with some appenders lets log4net queue up log entries and write them in a single go. If you are writing entries to the database then buffering is a good way to improve performance.
  • More platforms - Enterprise Library does not support the .NET Compact Framework while log4net does.

If you have any other thoughts on the Logging Application Block or log4net I'd love to hear them.