DropBox Removed their SSDs, got 20% faster writes

The Backend Engineering Show with Hussein Nasser

Episode | Podcast

Date: Tue, 24 Jan 2023 10:46:11 GMT

<p><a href="https://dropbox.tech/infrastructure/increasing-magic-pocket-write-throughput-by-removing-our-ssd-cache-disks">https://dropbox.tech/infrastructure/increasing-magic-pocket-write-throughput-by-removing-our-ssd-cache-disks</a></p> <p>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.</p> <p>0:00 Intro</p> <p>2:00 Article Summary</p> <p>3:00 SMR Drives</p> <p>6:00 SSD Cache &amp; WriteBack</p> <p>8:00 Replacing Cache</p> <p>9:30 Storage Engine Background</p> <p>14:30 Why did they do it</p> <p>15:00 The limitation of SSDs &amp; Zoned Namespaces</p> <p>19:30 Updating the Storage Engine</p> <p>22:30 Tradeoffs</p> <p>26:00 Rollout</p> <p>28:00 Summary</p>