CPU Cache Coherency

CPU cache coherency is the system of protocols that ensures all processors in a multi-core system see a consistent view of memory. When one core updates a value, the coherency protocol must update or invalidate copies of that data in other caches.

In high-performance trading, the overhead of maintaining coherency can be a major source of latency. Engineers must design software to minimize shared data access across cores, allowing each core to work as independently as possible.

Understanding how these protocols function is vital for building scalable, high-throughput financial systems that do not choke on synchronization overhead.