How would you design storage for distributed data logs supporting append-only writes, retention policies, partitioning, replication, and high-throughput sequential reads? Detail segment management, compaction, indexing, leader and follower roles, and recovery.

This question evaluates a candidate's expertise in designing distributed storage systems, covering partitioned append-only logs, high-throughput writes and reads, replication, retention, indexing, compaction, leader/follower roles, and recovery mechanisms.

How do I approach System Design interview questions?

System Design questions require understanding of core concepts and practice. PracHub provides solutions with explanations to help you master system design interviews.

What difficulty level is this interview question?

This is a hard difficulty System Design question, commonly asked during Technical Screen rounds at Google.

What role is this question designed for?

This question is commonly asked for Software Engineer candidates at Google during technical interviews.

Design distributed log storage service | Google Interview Question

Design a Distributed Append-Only Log Storage System

You are asked to design the storage layer of a distributed, partitioned, replicated append-only log service that supports:

Append-only writes with high throughput
Retention policies (by time and/or size)
Partitioning for horizontal scalability
Replication for fault tolerance
High-throughput sequential reads

Detail the following components and behaviors:

Segment management: active vs. sealed segments, rollover conditions, deletion, and preallocation.
Compaction: when and how to compact, tombstones/deletes, write amplification tradeoffs.
Indexing: offset-to-file-position index, time index, sparsity, and rebuild.
Leader/follower roles: write and read paths, quorum/ack semantics, high watermark, lag handling.
Recovery: crash recovery, index rebuild, truncation, leader election safety, and follower catch-up.

Assume a large-scale multi-node deployment with commodity disks and network, and that clients produce and consume records identified by monotonically increasing offsets within each partition.

Design a Distributed Append-Only Log Storage System

You are asked to design the storage layer of a distributed, partitioned, replicated append-only log service that supports:

Append-only writes with high throughput

Retention policies (by time and/or size)

Partitioning for horizontal scalability

Replication for fault tolerance

High-throughput sequential reads

Detail the following components and behaviors:

Segment management: active vs. sealed segments, rollover conditions, deletion, and preallocation.

Compaction: when and how to compact, tombstones/deletes, write amplification tradeoffs.

Indexing: offset-to-file-position index, time index, sparsity, and rebuild.

Leader/follower roles: write and read paths, quorum/ack semantics, high watermark, lag handling.

Recovery: crash recovery, index rebuild, truncation, leader election safety, and follower catch-up.

Assume a large-scale multi-node deployment with commodity disks and network, and that clients produce and consume records identified by monotonically increasing offsets within each partition.

Design distributed log storage service

Quick Overview

Design distributed log storage service

Design a Distributed Append-Only Log Storage System

Submit Your Answer to Earn 20XP

Design distributed log storage service

Quick Overview

Design distributed log storage service

Design a Distributed Append-Only Log Storage System

Submit Your Answer to Earn 20XP