Multi Step Processes medium
Service A calls Service B, which calls Service C. If Service C hangs, Service A eventually crashes due to thread exhaustion. How does a Circuit Breaker on Service A prevent this?
- A It restarts Service C.
- B It detects the failures/timeouts and 'Opens', failing fast without waiting for the timeout.
- C It creates more threads.
- D It queues the requests.
Answer: B. It detects the failures/timeouts and 'Opens', failing fast without waiting for the timeout.
Circuit Breakers prevent 'Cascading Failure'. Instead of waiting 30s for a timeout (and holding the thread), the breaker fails instantly (Fast Fail), keeping Service A responsive.
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