Linux CPU Isolation and NUMA Tuning: A Practical Guide to Exclusive Compute for Critical Workloads
Overview You’re running a high-frequency trading system online. P99 latency sits at 2ms normally, but occasionally spikes to 20ms. CPU usage isn’t high, memory is sufficient, network is fine. After investigation, you discover the CPU scheduler migrated a critical thread to another core, L3 cache missed entirely, and latency jumped 10x. This kind of problem can’t be solved by adding resources. The issue is “sharing” — all processes share CPU cores, the scheduler distributes freely, and nobody knows which threads are latency-sensitive....