CNS Lock: Compact NUMA-aware Lock with a Standard Interface

In recent years, multi-core systems with NonUniform Memory Access (NUMA) architectures are becoming prevalent. Multithreaded applications that execute on NUMA architectures play a pivotal role in getting better performance. The difficulties associated with multi-threaded applications are more pronounced because of compatibility issues with synchronization objects and the underlying NUMA architectures. Locks are fundamental synchronization primitives to avoid data races and achieve high performance in multi-core systems. With the increasing performance demands, locks have been refined and optimized with the architectural features of the NUMA systems. This paper proposes a novel synchronization object, namely CNS Lock (Compact NUMA-aware lock with a Standard interface) for NUMA systems. The CNS lock utilizes a single queue irrespective of the number of NUMA nodes and minimizes the number of atomic operations required for lock acquisition and release by prioritizing threads based on their NUMA node affinity. It considers the current thread’s NUMA node number to get the efficiency of a NUMA-aware design. CNS lock provides a standard interface to facilitate seamless integration into existing applications without knowing the internals. The CNS Lock strategically optimizes lock handovers and minimizes memory latency by employing a unified queue system across NUMA nodes. Our experimental results show that the CNS lock significantly outperforms the state-of-the-art locking mechanisms and makes it one of the essential tools of systems with NUMA architectures for better synchronization.