deterministic latency
Beginner
Taking exactly the same time, every time.
Novice
Delay that doesn’t vary with load or with what happened just before, because every operation takes a fixed number of clock ticks.
Expert
Achieved by removing queues, caches, arbitration and shared buses from the critical path. Residual variation comes from clock-domain crossings, serial-link alignment and off-chip memory.
Explained in Fintech and trading (Industries).