Quiescent state based reclamation/QSBR
preshing New Concurrent Hash Maps for C++ # Safe Memory Reclamation
All Junction maps rely on a form of safe memory reclamation known as QSBR, or quiescent state-based memory reclamation. QSBR could be described as a primitive garbage collector.
preshing Using Quiescent States to Reclaim Memory
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这篇文章对此进行了较好的分析