Slabs and segmented LRU, a ch3 pool behind mcrouter, leases against stale sets and herds, gutter and regional pools, deletes from the MySQL log and remote markers: one-hour boards for junior, senior and staff, with the theory.
Infrastructure, platform and reliability engineers.
Your approach: Use diagrams or prose to explain responsibilities, state, capacity and failure behavior. Show the calculations requested by the question.
Design a Distributed Cache like Memcached at Scale. Slabs and segmented LRU, a ch3 pool behind mcrouter, leases against stale sets and herds, gutter and regional pools, deletes from the MySQL log and remote markers: one-hour boards for junior, senior and staff, with the theory. Work from the scoping questions below. State assumptions for any unspecified load, guarantee or target, then trace your design end to end. Explain one difficult case and a credible alternative; the worked example is a reference, not a required implementation.
Resolve the scoping questions for a Distributed Cache like Memcached at Scale. Separate stated behavior from assumptions, and identify what is outside your design.
Declare relevant volume, latency, freshness, quality or cost targets with units. Show calculations or an evaluation plan that can test them; unspecified targets are your assumptions, not hidden pass criteria.
Explain how your guarantees hold in a difficult case relevant to this subject. Address: Value sizes? Hot keys?
Identify users, required behavior and exclusions. Answer: Scale? Access pattern?
Define the information owned by the system and the inputs, outputs and errors at its boundaries. Resolve: How stale? Where?
Estimate the dominant workload and resource demand with units and explicit assumptions. For a learned system, also state how quality is measured and what data is available.
Draw or describe the responsibilities needed for a Distributed Cache like Memcached at Scale. Trace a representative request, event or job from its input to a visible result; identify durable state owners.
Walk through a difficult case step by step, including detection and recovery. Consider: What may a server failure cost? Value sizes? Hot keys?
Compare a credible alternative using your chosen workload and guarantees. Explain a remaining risk, a signal to watch and when you would change the design.