4 ms·

I actually use it as primary database on some parts of the mmorpg I’m developing, Redis actually has ACID capabilities so it is actually very suitable to use a

I actually use it as primary database on some parts of the mmorpg I’m developing, Redis actually has ACID capabilities so it is actually very suitable to use as primary database in gaming platforms. That being said main game server requires Mongodb due to sheer size of the data.

takeda 6y ago
Well, if you have only a single instance that doesn't support threading it is trivial to get those properties, but what about durability? Do you realize you store all of the data in the RAM?
- latortuga 6y ago
  This is your second comment in this thread about Redis being in-memory. Redis can function in-memory only but it also has at least 2 persistence stories (rdb snapshots, aof logs), and out of the box is configured use rdb.
  - Scarbutt 6y ago
    Your data still has to fit in memory though.
- devit 6y ago
  Redis can dump and fsync data to disk WAL every query, and can run multiple commands in a transaction, so it can provide the highest guarantees possible for a database. The catch is that the data must fit in RAM, you can only use 1 core for query processing, there is no support for long-lived transactions and no built-in SQL support. Obviously in an ideal world something like Redis would be useless since proper databases would cover all use cases, but unfortunately the state of database software is disastrous.
- skrebbel 6y ago
  RAM is cheap and lots of realistic data sets never exceed some tens of GBs, even in extreme scenarios. What's wrong with keeping (a copy of) all data in RAM? It's what makes Redis fast yet simple.
  - takeda 6y ago
    Nothing wrong if it is a cache, I would have problem using it as a primary data store for important data as many do.
    - skrebbel 6y ago
      Here's a terrifying secret for you: if a dataset is small enough and used intensively enough, SQL databases like PostgreSQL will eventually have all of it in RAM. Better ditch those too!
    - dalyons 6y ago
      why? what is wrong with the persistence mechanisms it has?
- DethNinja 6y ago
  Redis got a feature called AOF, I use it for every single command to save the command history to disk. This does obviously decrease write performance of the Redis quite a bit, but read performance is mostly fine. It is all about how many writes versus reads you expect per second. My system expects at most 1 write per sec vs 100 reads, so performance is fine and this way it is ACID compliant.

takeda 6y ago

Well, if you have only a single instance that doesn't support threading it is trivial to get those properties, but what about durability? Do you realize you store all of the data in the RAM?

latortuga 6y ago
This is your second comment in this thread about Redis being in-memory. Redis can function in-memory only but it also has at least 2 persistence stories (rdb snapshots, aof logs), and out of the box is configured use rdb.
- Scarbutt 6y ago
  Your data still has to fit in memory though.
devit 6y ago
Redis can dump and fsync data to disk WAL every query, and can run multiple commands in a transaction, so it can provide the highest guarantees possible for a database. The catch is that the data must fit in RAM, you can only use 1 core for query processing, there is no support for long-lived transactions and no built-in SQL support. Obviously in an ideal world something like Redis would be useless since proper databases would cover all use cases, but unfortunately the state of database software is disastrous.
skrebbel 6y ago
RAM is cheap and lots of realistic data sets never exceed some tens of GBs, even in extreme scenarios. What's wrong with keeping (a copy of) all data in RAM? It's what makes Redis fast yet simple.
- takeda 6y ago
  Nothing wrong if it is a cache, I would have problem using it as a primary data store for important data as many do.
  - skrebbel 6y ago
    Here's a terrifying secret for you: if a dataset is small enough and used intensively enough, SQL databases like PostgreSQL will eventually have all of it in RAM. Better ditch those too!
  - dalyons 6y ago
    why? what is wrong with the persistence mechanisms it has?
DethNinja 6y ago
Redis got a feature called AOF, I use it for every single command to save the command history to disk. This does obviously decrease write performance of the Redis quite a bit, but read performance is mostly fine. It is all about how many writes versus reads you expect per second. My system expects at most 1 write per sec vs 100 reads, so performance is fine and this way it is ACID compliant.