How do distributed systems handle resource sharing?

Distributed systems handle resource sharing through a coordinated approach that involves communication, synchronization, and sometimes replication.

In a distributed system, multiple independent computers, known as nodes, are linked together to work as a single system. These nodes share resources such as processing power, memory, and data storage. The main challenge in resource sharing in distributed systems is ensuring that all nodes can access the resources they need without conflicts or inconsistencies. For an in-depth look at the differences between centralised and distributed systems, you can refer to our notes on centralised vs distributed systems.

One way distributed systems handle resource sharing is through communication. Nodes in a distributed system communicate with each other to coordinate their actions and share resources. This communication can take various forms, such as message passing, where nodes send messages to each other to request resources or inform others of their actions. Another form of communication is remote procedure calls, where a node can request a service from another node by calling a procedure on that node. Understanding the pros and cons of wireless networks can provide further insight into how communication can vary in different network setups.

Synchronization is another crucial aspect of resource sharing in distributed systems. It ensures that all nodes have a consistent view of the shared resources. For example, if two nodes try to access the same resource at the same time, a synchronization mechanism can ensure that only one node accesses the resource at a time, preventing conflicts. Synchronization can be achieved through various mechanisms, such as locks, semaphores, or timestamps. The role of the operating system in resource management is vital in this context, as it often handles these synchronisation tasks.

In some cases, distributed systems handle resource sharing through replication. This involves creating copies of a resource on multiple nodes. Replication can improve the availability and reliability of resources, as even if one node fails, the resource is still available on other nodes. However, replication also introduces the challenge of maintaining consistency across the replicas. This is typically handled through replication protocols, which ensure that all replicas have the same state.

IB Computer Science Tutor Summary: Distributed systems share resources by using communication, synchronisation, and replication. Nodes communicate to coordinate actions and share resources, ensuring no conflicts. Synchronisation keeps the view of resources consistent, preventing simultaneous access conflicts. Replication involves creating copies of resources on multiple nodes to improve availability and reliability, though it requires protocols to maintain consistency.