US Patent 10885022 Log-structured storage systems

Disclosed herein are methods, systems, and apparatus, including computer programs encoded on computer storage devices, for data processing and storage. One of the systems includes a multi-tier storage subsystem including multiple tiers of storage devices, an input/output (I/O) subsystem that is configured to perform a write operation of blockchain data into a data log file, and a back-end data management subsystem that is configured to perform a management operation of the data log file stored in the one of the multiple tiers of storage devices.