Counter array false sharing
Review this C++ per-thread counter array used to aggregate stats across N worker threads. Each worker increments its own slot in a tight loop, then a reader sums them.
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1struct Counters {
2 std::atomic<long> hits[64]; // one slot per worker thread
3};
4
5void worker(Counters& c, int id) {
6 for (int i = 0; i < 100000000; ++i)
7 c.hits[id].fetch_add(1, std::memory_order_relaxed);
8}
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