Abstract: A key-value store and a file system are integrated together to provide improved operations. The key-value store can include a log engine, a hash engine, a sorting engine, and a garbage collection manager. The features of the key-value store can be configured to reduce the number of I/O operations involving the file system, thereby improving read efficiency, reducing write latency, and reducing write amplification issues inherent in the combined key-value store and file system.

Abstract: Decoupled computing systems include layers of same-type computing resources, and include a dispatch layer to assign tasks from one layer to another, such as input and output (I/O) flows. The I/O flows can be assigned to particular computing resources of a layer based on a weighted moving average of performance data for the layer. When traffic is high, the assignment can include random assignment to some or all of the computing resources in the layer. The I/O flows can be split between read-intensive and write-intensive flows, with more read-intensive flows being assigned based on a pick ratio.

Abstract: A file system particular for use with key-value stores is provided. The file system can operate in a user space instead of a kernel space. The file system can be an append-only file system. The file system can support use of solid state drives (SSDs) for storage, including zoned SSDs. The file system can include a file manager, a metadata manager, a task scheduler, a space allocator, and a collaborator for collaborating with a key-value store.

Abstract: Methods and systems of a log engine for logging data operation in a file system is disclosed. The log engine includes a user interface module configured to receive a plurality of data operation logs that respectively record a data operation and a sequence ID corresponding to an order of the data operation being performed; and a shared log manager configured to provide an in queue configured to consolidate the plurality of data operation logs, and swap the plurality of data operation logs to an out queue with the plurality of data operation logs being ordered based on the sequence ID and saved in a shared log.