In-Memory Key-Value Store with Crash Recovery from a Log and Concurrent Access
Company: OpenAI
Role: Software Engineer
Category: Software Engineering Fundamentals
Difficulty: hard
Interview Round: Onsite
Overview: Implement an in-memory key-value store, make it recover from a log file after a crash, including a half-written final record, and make it correct and fast under many concurrent threads. It tests write-ahead logging, crash consistency, compaction, and lock design with group commit.