Building a Next-Generation Key-Value Store at Airbnb

How we completely rearchitected Mussel, our storage engine for derived data, and lessons learned from the migration from Mussel V1 to V2. By Shravan Gaonkar , Chandramouli Rangarajan , Yanhan Zhang How we completely rearchitected Mussel, our storage engine for derived data, and lessons learned from the migration from Mussel V1 to V2. Airbnb’s core key-value store, internally known as Mussel, bridges offline and online workloads, providing highly scalable bulk load capabilities combined with single-digit millisecond reads. Since first writing about Mussel in a 2022 blog post , we have completely deprecated the storage backend of the original system (what we now call Mussel v1) and have replaced it with a NewSQL backend which we are referring to as Mussel v2. Mussel v2 has been running successfully in production for a year, and we wanted to share why we undertook this rearchitecture, what the challenges were, and what benefits we got from it. Why rearchitect Mussel v1 reliably supported