I have a question that is bugging me quite heavily. What is the Redis pub/sub feature actually used for? I can only think of inter-process communication over TCP (either locally or distributed), however not much else.
Can someone please prove me wrong.
It's an easy way to plug into an event stream, generally between processes or machines. For instance, an user creates a published event. One process handles updating the database from the event, another updates user stats, another global stats, another updates the text search database, etc. They're all loosely coupled by subscribing to the channel. You can add new processes for testing updates and monitoring the system. It's a little different from a message queue in that there's no storing messages until they're processed, but Redis has other structures for those sorts of jobs.