December 2023
Intermediate to advanced
464 pages
12h 35m
English
Content preview from Patterns of Distributed Systems
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Chapter 26
Lease
Use time-bound leases for cluster nodes to coordinate their activities.
Problem
Cluster nodes need exclusive access to certain resources. But nodes can crash, be temporarily disconnected, or experience a process pause. Under these error scenarios, they should not keep the access to a resource indefinitely.
Solution
A cluster node can ask for a lease for a limited period of time, after which it expires. The node can renew the lease before it expires if it wants to extend the access. Implement the lease mechanism with Consistent Core to provide fault tolerance and consistency. Have a time-to-live value associated with the lease. Cluster nodes can create keys in a Consistent Core with a lease attached to it.
The leases are replicated ...