Java · Senior · Theory

What is the Java Memory Model, and what is the happens-before relationship? Tell me what guarantees volatile gives and where it isn't enough.

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This checks whether you understand that the JMM is a formal contract of visibility and ordering between threads, not the layout of the heap and the stack. The second thing it checks: whether you know the exact limits of volatile, which gives you visibility and ordering but not atomicity of compound operations.

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concurrency memory model

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