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Java / JVM Architecture (Java21) Interview questions

What are Native Method Stacks?

Native Method Stacks are per-thread memory areas used specifically when a thread executes a native (non-Java) method, typically C or C++ code reached through the Java Native Interface (JNI).

They exist separately from the regular JVM Stack because native code frames follow the calling conventions of the native language and platform, not the JVM's bytecode-based frame layout.

Some JVM implementations combine the native stack with the OS thread stack instead of keeping a fully separate structure, since native code already runs directly on the underlying platform.

Native Method Stacks are used when a thread executes:
Native Method Stacks are separate from the JVM Stack because:

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