Difference Between Hazelcast vs Redis

Hazelcast and Redis are the two preferred choices for in-memory databases. They look quite similar if a beginner is looking at them. They have similar use cases but experienced ones can find out the difference between them and use them according to their requirements. They work quite differently in many aspects. Let us look at the aspects in which they differ.

Hazelcast

Hazelcast is a distributed In-Memory Data Grid platform for Java. It supports high scalability and data distribution in a clustered environment. Basically, it is a very useful tool in developing applications that require high scalability, performance, and availability.

Advantages

1. There are no external dependencies.
2. It offers the same interfaces and APIs as the Java util package.
3. It stores and processes equal amounts of data for each member.

Disadvantages

1. It has high memory consumption.
2. Implementation of a memory-sharing system is difficult.
3. It runs in a virtualization environment.

Redis

Redis stands for Remote Dictionary Server for real-time applications that can handle millions of queries per second. It was developed by Salvatore Sanfilippo. The distribution and delivery of messages to subscribers are because of its pub/sub messaging technique.

Advantages

1. It offers low latency and fast data access as all the data stays in memory.
2. There are no external dependencies.
3. It is compatible with other languages, including Java, JavaScript, Python, Ruby, and PHP. 
4. It is a good option for real-time analytics.

Disadvantages

1. It has limited memory storage.
2. It has no support for query language and relational algebra.
3. It is not quite flexible.

Difference between Hazelcast and Redis-

Parameters	Hazelcast	Redis
Written and Implementation	In Java.	In C.
Remove Node data	Shut down the node, and the data is saved.	The node data is removed first, and then it is shut down.
Replication	Large data is loaded because replication is not turned off.	Large data is loaded because replication is turned off.
Clustering	Most operations are handled automatically.	Operations are done manually.
Performance	Performance is better.	Performance is not good as compared to Hazelcast.
Data backup	In hazelcast, data is its own backup.	Each file in Redis is backed up by another database.
Physical Machines	It uses less number of physical machines.	It uses a high number of physical machines than Hazelcast.
Querying	It understands complex object graphs and provides querying API.	It does not understand complex object graphs and provides querying API.
Failures	It uses peers to detect member failures.	Uses sentinel to detect member failure.
Standard Serialization	Standard Serialization takes time in Hazelcast.	Standard Serialization is faster in Redis than in Hazelcast.
Streaming	Comes with a full streaming stack for streaming.	Supports pub-sub messaging to distribute streaming data.
Library support	There are not many libraries available in Hazelcast which is why it uses only javalibs.	Redis supports many libraries.
Documentation	The documentation is less because it is new in the market as compared to Redis.	The documentation is well-maintained for Redis.
Management	It is not managed properly.	It is managed properly.

Though both seem to be quite popular and similar yet they are different in many aspects. Redis is a very popular open-source platform and is used widely in the market. If one only needs simple caching and not clustering, querying & computation, then Redis is the best option for the user. Hazelcast is also a developer-friendly data-grid solution. Both have their own pros and cons. It all depends on the organization to choose which platform is according to their own requirements.

Hazelcast and Redis are both popular open-source distributed caching and data management solutions, but they have some key differences in terms of their architecture and functionality. 

Here are some of the main differences between Hazelcast and Redis:

• Architecture: Hazelcast is a distributed in-memory data grid (IMDG) while Redis is an in-memory key-value store. Hazelcast distributes data across multiple nodes in a cluster while Redis runs on a single node.
• Data Model: Hazelcast supports distributed maps, sets, queues, and other data structures, while Redis supports a wider range of data types, including strings, hashes, lists, sets, and sorted sets. Redis also provides more advanced features like transactions and Lua scripting.
• Performance: Both Hazelcast and Redis are designed for high performance, but Hazelcast is optimized for in-memory storage and processing, while Redis can also persist data to disk.
• Clustering: Hazelcast provides built-in clustering capabilities with automatic discovery and node management, while Redis requires third-party clustering solutions for high availability.
• Integration: Hazelcast provides integrations with popular Java frameworks like Spring and Hibernate, while Redis has a broader range of client libraries for multiple programming languages.

Overall, Hazelcast is more focused on in-memory data management and distributed computing, while Redis is a more versatile data store with advanced features and broader language support. The choice between these two solutions will depend on the specific requirements of your application and the features that you need.