Shareability Domains

Defining "Who needs to know" about data changes. Not every core needs to snoop every other core.

The Four Domains

To save power and time, ACE divides the Soc into domains:

Non-shareable: Just for me. No one else has a copy.
Inner Shareable: A group of friends (e.g., Cores in the same cluster). Changes are broadcast here.
Outer Shareable: Everyone else in the Soc (e.g., GPU, DMA).
System: Everyone, including main memory.

Barriers

Barriers are "Wait" signs. They ensure that all previous memory operations are finished before the next ones start. This is critical for data consistency in multi-threaded code.

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