Difference between Redis AOF and Tarantool WAL log

Question

I was reading this article about Tarantool and they seem to say that AOF and WAL log are not working the same way.

Tarantool: besides snapshots, it has a

Answer 1

AOF is the main persistence option for Redis. Any time there's a write operation that modifies the dataset in memory, that operation is logged. So during a restart, Redis will replay all of the operations to reconstruct the dataset. You also have 3 different fsync configuration policies to choose from (no, everysec, always). FWIW, it is usually advised to use both AOF + RDB in the event you want a good level of data-safety. This is kind of outside of the scope of your question, but figured i'd mention it.

Main Redis Persistence Docs

Redis Persistence Demystified

Tarantool's uses something called a "WAL writer". This will run in a separate thread and log requests that manipulate data "insert and update requests". On restart, Tarantool recovers by reading the WAL file and replaying each of the requests.

Tarantool Persistence Docs

There's a difference in the internals obviously, but at a high level they are pretty similar. The persistence comparison in the article is pretty odd and simply not true.

For more information on the low level differences, refer to the docs listed above.

Hope that helps