The current stable version of Redis is 6. Many Linux distros still
ship with version 5. Both talk protocol version 2. Version 6 also
supports protocol version 3. The main differences are:
- The version 3 protocol has several improvements that notably
improvement passing large objects using a streaming protocol.
- Hashes (maps) in the version 3 protocol are exchanged as lists of pairs
(
Name-Value), while version 2 exchanges hashes as a list of
alternating names and values. This is visible to the user. High level
predicates such as redis_get_hash/3
deal with both representations.
- The version 3 protocol supports push messages to deal with
monitor and subscribe events on the same connection as
used for handling normal requests.
New projects are encouraged to use Redis version 6 with the version 3
protocol. See redis_server/3.
