In this episode of the backend engineering show I’ll discuss how Dropbox improved their write through put by 20% by removing all their SSDs (yes I was surprised too). DropBox uses an SSD layer as a write-back cache with SMR drives as their backend persistent storage. They changed their model to write directly to the hard drives.
0:00 Intro
2:00 Article Summary
3:00 SMR Drives
6:00 SSD Cache & WriteBack
8:00 Replacing Cache
9:30 Storage Engine Background
14:30 Why did they do it
15:00 The limitation of SSDs & Zoned Namespaces
19:30 Updating the Storage Engine
22:30 Tradeoffs
26:00 Rollout
28:00 Summary