20 System Design Concepts Every Developer Should Know - Part - II

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Lets continue our learning journey from Part 1 :

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11. Phi Accrual Failure Detection

Phi Accrual Failure Detection is an adaptive Failure Detection algorithm that provides a building block to implementing failure detectors in any distributed system. A generic Accrual Failure Detector, instead of providing output as a boolean (system being up or down), outputs the suspicion information (level) on a continuous scale such that higher the suspicion value, the higher are the chances that the system is down.

Example: Akka uses the Phi Accrual Failure Detector to monitor the health of nodes in a distributed actor system.