What are the Devops-related conferences happening around the world?
Velocity Conference is one of the most popular Devops conferences, and also is an O'Reilly conference.

From it's website: 


  At Velocity, systems, site reliability, and systems engineers, systems
  architects, and application developers learn to build and manage fast,
  resilient, and highly available websites and apps.


The videos of the conference are present on O'Reilly's youtube channel.