Are Redis updates synchronous?

Question

If I push something onto a list in Redis, then pop from that list, is it guaranteed that I will get the item I pushed earlier or is it possible for the read to happen before the write?

Answer 1

Redis runs in a single thread (with the exception of forking when doing background saves, but that doesn't matter), so any request that you send later will necessarily run later. Thus, you will see the value that you pushed.

(Though, on a second thought, it is probably possible to provoke a failure, if you are ill inclined and dedicated to make it fail on purpose. But that would require sending your requests via separate connections, which doesn't happen accidentially in normal operation.)