Simon Willison’s Weblog


1 item tagged “online”


Redis in Practice: Who’s Online? Using Redis to implement a “which of your friends are online now” feature, by maintaining a set of active user IDs for every minute, then intersecting the past five minutes of user IDs with a set containing the IDs of your friends.

# 14th February 2010, 5:17 pm / friends, lukemelia, online, redis, social