In distributed robotics, there's a lot of things that go 1) pull data, 2) check timestamp on data to see if it's "fresh enough" to be considered.<p>Redis solves that so naturally with TTL that it's not even worth considering message queues, dbs, or ROS topics for this. Yet, almost nobody does it that way from what I can see (I mean, we did, and it was fine).
I used to use Redis for every project, but a lot of times just using a SQL database is fast enough.
Redis is wonderful, and simple but is yet another thing running and has to be checked and invalidated.