SMR: What we learned in our first year

This post details Dropbox's first year of adopting Shingled Magnetic Recording (SMR) technology for its Magic Pocket storage. Key contributions include: implementing software changes such as an SSD staging layer to handle SMR's sequential write limitations, leveraging the immutable block architecture for compatibility, and collaborating with hardware vendors to adapt chassis and firmware. The team also contributed to open-source libraries (libzbc) and developed a testing tool (SMRtest). The adoption resulted in increased storage density (surpassing 25% SMR capacity goal), significant cost savings (10-20% more data per drive, >20% overall savings), and energy efficiency improvements.