What is the major difference between Redis and Mem

问题:

What are the major differences between Redis and Membase?

回答1:

Scalability: Membase offers a distributed key/value store (just like Memcache), so writes and reads will always be performed in predictably constant time regardless of how large your data set is. Redis on the other hand offers just master-slave replication, which speeds up read but does not speed up writes.

Data Redundancy It's simple to setup a cluster with a set amount of replicated copy for each key-value pair, allow for servers to failover a inoperative node in a cluster without losing data. Redis' master-slave replication doesn't offer this same type of data redundancy, however.

Data Type: Redis offers ability to handle lists in an atomic fashion out of the box, but one can implement similar functionality in the application logic layer with Membase.

Adoption: Currently Redis is more widely adopted and a bit more mature than Membase. Membase does have a few high profile use case, such as Zynga and their slew of social games.

Membase has recently merged with Couchbase and they will have a version of Membase that will offer CouchDB's Map/Reduce and query/index ability in the next major release (scheduled around early 2011).

回答2:

Membase is a massive key-value store with persistent and replication for failover. The data stored in membase is not subject to "modification" (besides increment). You get or set it.

Redis is more of a key-data store. Redis allows the manipulation of sets, lists, sorted-lists, hashes and some odd other data types. While redis has replication it is more of a master/slave type of replication.

回答3:

I'm adding some points to Manto's answer:

1. Redis has built in transaction mechanism, while membase does not. Base on your work it may be critical
2. Master-master replication have some cons compare to master-slave: loosy consistent (lazy object, async...), more complex compare to master-slave (hence add some latency).
3. Current version of redis (2.x) does not support clustering. You'll need to shard the database manually (check http://antirez.com/post/redis-presharding.html), while membase support clustering out of the box and have a pretty nice monitoring gui.
4. (Benchmark may be ** but people just love dirty things) Redis seems to have slight performance edge at heavily concurrent case. (http://coder.cl/2011/06/concurrency-in-redis-and-memcache/)