FoundationNumeric answer
Per-thread counters · Part 1 of 3
Sixteen worker threads count the messages they handle in std::atomic<uint64_t> counts[16], a contiguous array that starts on a 64-byte cache-line boundary. Each thread increments only its own element.
Counting thread 0 itself, how many threads write into the cache line that holds counts[0]?
Answer with a number. Fractions, powers and expressions like 23/6 or C(52,5) are read correctly in practice.
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