US Patent 11550479 Metadata management in storage systems

Techniques are disclosed for managing metadata of a storage system. A storage control system receives data to be written to primary storage, and writes the received data together with metadata to a write cache. The storage control system destages the metadata from the write cache to a primary metadata structure which is configured to persistently store and index the metadata. The primary metadata structure comprises (i) a first data structure that is configured to accumulate the metadata destaged from the write cache and organize the accumulated metadata in blocks of metadata sorted by index keys, and (ii) a second data structure that is configured to receive the accumulated metadata from the first data structure, and organize the received metadata using an index structure that enables random-access to the metadata using the index keys.