Lock-Free Queues Are Lying to You. Wait-Free Is the Real Gold Standard.
Lock-free queues are widely considered the performance ceiling for concurrent data structures. They’re not. Under real contention, CAS retry storms crater throughput while burning CPU. Wait-free MPMC queues eliminate retries entirely—every operation completes in bounded steps regardless of load. The result is 2-3x throughput under high contention, plus correctness guarantees that lock-free can’t match. If you write multi-threaded code for HFT, game engines, or real-time systems, lock-free isn’t your gold standard. It’s your bottleneck.