Journaling vs Transactional Files Systems

Journaling vs Transactional Files Systems


As end-user expectations rise and embedded devices get more complex, reliable file management is rapidly becoming a commonplace requirement. The file systems available in most embedded operating systems were not specifically designed with the needs of the embedded marketplace in mind, but instead evolved out of solutions developed for desktop and server environments. These file systems have significant shortcomings in embedded devices: 

  1. They were not designed for use in an environment where power may be lost.
  2. The error recovery processes are slow, which is typically not acceptable when “instant-on” is the user’s expectation.
  3. Desktop and server file systems were not designed for use in an environment with limited resources such as is often found in embedded devices.

This white paper looks at the limitations of desktop/server file systems in embedded devices, and then reviews the operation of two different solutions—journaling and transactional file systems— and the key differences between them. 

Note: The paper assumes familiarity with file system basics. File system concepts are covered in Appendix A for those new to the topic.