Hyperloglog

Facebook Algorithm to count distinct elements — Approximation Algorithm

Simplifies cardinality estimation, or count-distinct problem. Ex count number of views on a webpage. Takes input data and hashes it


Pull vs Push vs Poll — A NewsFeed Perspective

Curated list of information from HighScalablity Facebook Twitter

Polling

  • Every page that had commentable content, the page would periodically send request until new content arrived , get real…