Near-real-time garbage collection

Real-time systems tend to fit badly in a garbage collecting world. No matter how well a garbage collector performs, we still have a non-deterministic runtime overhead. Even if the latencies introduced by the GC are few and stopping the world completely is a rare event, a certain degree of non-determinism cannot be avoided.

So what do we mean by real-time? The terminology suffers from a certain degree of misuse. To avoid some of the confusion associated with real-time, we will divide the concept into hard real-time and soft real-time.

Hard and soft real-time

Hard real-time should be understood as the more traditional real-time system—perhaps a synthesizer or a pacemaker, a system where 100 percent determinism is ...

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