InterviewStack.io LogoInterviewStack.io

CAP Theorem and Consistency Models Questions

Understand the CAP theorem and how Consistency, Availability, and Partition Tolerance interact in distributed systems. Know different consistency models including strong consistency such as linearizability, eventual consistency, causal consistency, and session consistency, and how to apply them to different use cases. Be familiar with consensus protocols and distributed coordination primitives such as Raft and Paxos, quorum reads and writes, two phase commit and when to use them. Understand trade offs between consistency and availability under network partitions, patterns for hybrid approaches where different data uses different guarantees, and the product and developer experience implications such as latency, stale reads, and API contract clarity.

MediumTechnical
0 practiced
A distributed system uses leader election via Zookeeper. Explain how ephemeral znodes and session timeouts work to prevent split-brain and what operational knobs you would tune when experiencing false leader elections due to network flakiness.
HardTechnical
0 practiced
Describe how you would run an experiment to measure the fraction of stale reads produced by a candidate eventually-consistent backend. What instrumentation would you add to clients and servers, and what statistical methods would you use to interpret results?
HardTechnical
0 practiced
Describe an approach to implement 'read-repair' proactively (background reconciliation) in a distributed store without impacting foreground read latency. How would you schedule repairs, prioritize hot keys, and ensure repairs converge safely?
HardTechnical
0 practiced
Explain how linearizability differs from serializability and snapshot isolation. Give an example of a workload where linearizability is sufficient but serializability is not necessary, and vice versa.
EasyTechnical
0 practiced
Define and differentiate between strong consistency (linearizability), eventual consistency, causal consistency, and session consistency. For each model give a one-sentence real-world example where a data engineer would prefer that model.

Unlock Full Question Bank

Get access to hundreds of CAP Theorem and Consistency Models interview questions and detailed answers.

Sign in to Continue

Join thousands of developers preparing for their dream job.