Hash Map Memory Reclamation for Lock-Free Parallel Reads

The patent extracts the locking mechanism from the memory access path by implementing lock-free data structures. Instead of using read/write locks to protect hash map operations, the invention uses atomic compare-and-swap instructions and versioning to ensure data consistency without requiring thread blocking or synchronization primitives, thereby eliminating the performance overhead while maintaining reliability

The patent replaces the mechanical locking system (read/write locks that block threads) with an atomic instruction-based system. The invention uses hardware-supported atomic operations (compare-and-swap) and software-generated version tags to achieve synchronization-free concurrent access, substituting the traditional mechanical synchronization approach with a more efficient atomic operation-based approach

The patent applies preliminary action by pre-allocating additional memory space before it is needed. When a hash map bucket reaches its capacity, the system proactively allocates a new, larger bucket and begins transferring elements, rather than waiting until memory pressure occurs. This advance preparation allows smooth transitions and prevents race conditions during memory reallocation

The patent implements dynamic memory management where hash map buckets can grow and shrink based on actual usage patterns. The system dynamically adjusts bucket sizes and reallocates memory as needed, using reference counting and atomic operations to ensure that memory is freed only when no longer needed by any thread, thus optimizing utilization while maintaining consistency