Latency Budget Quant Interview Guide
Latency budget quant interview guide for decomposing total latency, measuring percentiles, finding bottlenecks, and explaining tradeoffs.
Candidates discussing performance targets for trading and data systems.
Budgets decompose a path
A latency budget breaks total delay into feed handling, normalization, strategy logic, risk checks, order gateway, network, and venue response. The split makes bottlenecks visible.
Percentiles beat averages
Mean latency can hide tail behavior. In trading systems, p95, p99, max, and distribution shifts may matter more than a single average number.
Concrete example
If total p99 latency rises, compare component timings before and after the change. A queue or garbage-collection pause may be more important than strategy math.
Budgets guide engineering tradeoffs
A component over budget can be optimized, moved off the hot path, simplified, or accepted if risk and business requirements allow. State the tradeoff.
Common mistakes
Candidates often invent latency targets without context. A stronger answer explains measurement, decomposition, tail behavior, and why a target matters.
Practice the pattern
Use the LeetQuidity curriculum and calibration to turn this topic into a focused practice plan.