Hazelcast

Overview

Hazelcast is an in-memory data grid (IMDG) that provides distributed data structures and computing capabilities to manage the distributed cache. The in-memory distributed cache is stored across the cluster of nodes. It is designed and helps applications achieve high performance, scalability, and reliability. Hazelcast supports multiple programming languages For example – Java, Python, etc.

What is Hazelcast?

Hazelcast is one of the distributed In-Memory Data Grid platform for Java application. The architecture supports high scalable and data distribution in a clustered environment which is called nodes. It supports the auto-discovery of nodes and serializes and desterilizes the data.

Hazelcast offers multiple features such as Distributed Data Structure, Compact Serialization, Distributed Compute, Distributed SQL Query, Predicates etc.

Key Features of Hazelcast

• In-memory Data Store: Hazelcast stores data in memory, making data access very fast. This allows your application to run faster by avoiding disk I/O overhead.
• Distributed Caching: Hazelcast distributes your data across multiple nodes, which balances the load and keeps the data safe in case of failure of any node.
• Scalability: You can easily scale the Hazelcast cluster by adding more nodes, which makes your system ready to handle large-scale workloads.
• Fault Tolerance: If a node fails, Hazelcast automatically replicates the data and recovers to continue the system.
• Real-time Processing: Hazelcast provides high-speed, real-time data processing, which is very useful in applications such as financial services, e-commerce, or IoT systems.
• Simplified Development: Hazelcast’s API is quite simple to use, and is available in Java, Python, C++, and .NET. This makes it easy for developers to integrate their applications with distributed systems.

Core Components of Hazelcast

• Hazelcast Instance: The core unit of Hazelcast is the HazelcastInstance, which represents a single node in a Hazelcast cluster. It contains data structures and services that the application interacts with.
• Data Structures: Hazelcast provides distributed versions of common data structures:
  • IMap: Distributed hash map.
  • IQueue: Distributed queue.
  • ISet: Distributed set.
  • MultiMap: A map that can hold multiple values for a single key.
• Hazelcast Clusters: A group of Hazelcast instances working together forms a cluster. Data and tasks are distributed across the nodes in this cluster.

How Hazelcast Works

When you deploy Hazelcast in a cluster:

• Data Distribution: Hazelcast divides the data into partitions and spreads these partitions across the nodes in the cluster. Each node is responsible for a portion of the data.
• Replicas: Hazelcast creates backups (replicas) of each partition on different nodes to ensure data availability in case of a node failure.
• Load Balancing: As new nodes are added, Hazelcast automatically rebalances the data across the cluster to optimize performance.

Use Cases for Hazelcast

• Caching: Hazelcast is often used as a distributed cache to store frequently accessed data in memory, reducing the load on databases and speeding up application performance.
• Session Management: Web applications can use Hazelcast to manage user sessions in a distributed manner, ensuring high availability and scalability.
• Real-Time Analytics: Hazelcast’s in-memory processing capabilities make it ideal for applications requiring real-time data analytics and processing.
• Microservices: Hazelcast is well-suited for microservices architectures, providing a shared data layer across services.