[Links of the day] 28/03/2016: Hierarchy of engagement, Latency measurement, TAO consistency at Facebook

• The Hierarchy of Engagement : Another excellent Greylock partners's slides deck on how to leverage the Hierarchy of Engagement to fuel the growth of your company.The proposed hierarchy model has three levels: 1) Growing engaged users, 2) Retaining users, and 3) Self-perpetuating.
• Measuring and Understanding Consistency at Facebook : paper summary of Facebook highly consistent DB : TAO. Interesting thing is that they have a hierarchical consistency model with synchronous cache consistency and asynchronous cache, DB/storage invalidation model.
• How NOT to Measure Latency : in-depth overview of Latency and Response Time Characterization, including proven methodologies for measuring, reporting, and investigating latencies, and overview of some common pitfalls encountered (far too often) in the field