Timeouts and Deadline Propagation

1. The Rule With No Exceptions

A timeout is the longest time a caller will wait for an answer before it treats the call as failed. Here is the rule, stated the way you should state it in an interview: every network call has a timeout, chosen on purpose.

A call with no timeout waits forever by default. Forever is exactly the resource-holding behavior that the previous lesson showed cascading into outages. The caller keeps a thread and a connection tied up while nothing comes back.