Gearman vs MQTT: What are the differences?

Introduction

Gearman and MQTT are two distinct technologies commonly used in the realm of distributed systems and messaging. Key differences exist between these two systems that impact their use cases and functionalities.

1. Communication Protocol: Gearman utilizes a client/server model with TCP-based communication between clients and workers, allowing for distributed processing of tasks. In contrast, MQTT is a publish/subscribe messaging protocol based on the lightweight, event-driven MQTT protocol, facilitating real-time messaging between clients.

2. Use Case: Gearman is primarily used for distributing tasks across multiple machines in a network, providing a framework for parallel computing and load balancing. On the other hand, MQTT is ideal for scenarios requiring real-time communication and data exchange, such as IoT devices, sensor networks, and mobile applications.

3. QoS Levels: MQTT supports three levels of Quality of Service (QoS) for message delivery - 0, 1, and 2, offering varying levels of reliability. Gearman, however, does not have built-in support for different QoS levels as it focuses on task distribution and execution.

4. Message Format: In Gearman, tasks are submitted as jobs with defined workloads, making it suitable for discrete computing tasks with structured inputs and outputs. MQTT allows for the transmission of messages in a lightweight, flexible format, making it adaptable to diverse data types and payloads.

5. Scalability: Gearman's architecture allows for easy scaling by adding more workers to handle an increased workload, making it a suitable choice for expanding computing capabilities. MQTT's pub/sub model enables horizontal scaling by adding more brokers to manage a growing number of clients and messages in a distributed system.

6. Persistence: MQTT supports persistent messaging, ensuring that messages are stored and delivered to subscribers even if they are offline during publication. Gearman, focused on task execution, does not inherently provide persistent storage or message buffering capabilities for tasks.

In Summary, Gearman and MQTT differ in their communication protocols, use cases, QoS levels, message formats, scalability options, and persistence features, catering to distinct requirements in distributed computing and real-time messaging applications.