Help me choose a key / value store

Question

Do not pay attention to others doing my research for me, but perhaps there was a kind soul who knows the answer from his head:

I need a key / value store with the following characteristics:

• Distributed
• You can iterate over the keys in ascending order.
• You can find the key based on the partial key (prefix).
• Values ​​can be blobs up to mb or two.
• Available with Java.
• Some way to set rules so that I can control how keys are distributed between machines, that is, I would like to have a rule that keys with a common prefix remain on the same machine.
• A way to query the system to find out which machine has a key.
• Some support for replication and redundancy.

Answer 1

I have two answers for you:

• Amazon S3 supports all of this, but it obviously works on its servers, not yours. In particular, it supports prefix search queries very well.
• MongoDB supports all of this. You can use regular expressions or $ where you need to use the prefix. Be careful with indexes for better performance.

Answer 2

I'm not sure if it meets all your requirements, but have you looked at the distributed Hazelcast cards ? It has been a while since I looked at Hazelcast, so I don’t know if there is a way to find out which instances are responsible for a given key, or a way to assign keys to instances, but it provides support for secure parallel operations throughout the distributed card and others pleasant things.