Resources of an address space are managed in dynamically sized ranges, extents, sets, and/or blocks. The address space may be divided into regions, each corresponding to a different, respective allocation granularity. Allocating a block within a first region of the address space may comprise allocating a particular number of logical addresses (e.g., a particular range, set, and/or block of addresses), and allocating a block within a different region may comprise allocating a different number of logical addresses. The regions may be configured to reduce the metadata overhead needed to identify free address blocks (and/or maintain address block allocations), while facilitating efficient use of the address space for differently sized data structures.

Systems and methods for storage allocation

A de-duplication is configured to cache data for access by a plurality of different storage clients, such as virtual machines. A virtual machine may comprise a virtual machine de-duplication module configured to identify data for admission into the de-duplication cache. Data admitted into the de-duplication cache may be accessible by two or more storage clients. Metadata pertaining to the contents of the de-duplication cache may be persisted and/or transferred with respective storage clients such that the storage clients may access the contents of the de-duplication cache after rebooting, being power cycled, and/or being transferred between hosts.

Systems and methods for a de-duplication cache

An apparatus, system, and method are disclosed for data block usage information synchronization for a non-volatile storage volume. The method includes referencing first data block usage information for data blocks of a non-volatile storage volume managed by a storage manager. The first data block usage information is maintained by the storage manager. The method also includes synchronizing second data block usage information managed by a storage controller with the first data block usage information maintained by the storage manager. The storage manager maintains the first data block usage information separate from second data block usage information managed by the storage controller.

Apparatus, system, and method for data block usage information synchronization for a non-volatile storage volume

An apparatus, system, and method are disclosed for an caching data using a solid-state storage device. The solid-state storage device maintains metadata pertaining to cache operations performed on the solid-state storage device, as well as storage operations of the solid-state storage device. The metadata indicates what data in the cache is valid, as well as information about what data in the nonvolatile cache has been stored in backing store. A backup engine works through units in the nonvolatile cache device and backs up the valid data to backing store. During grooming operations, the groomer determines whether the data is valid and whether the data is discardable. Data that is both valid and discardable may be removed during the grooming operation. The groomer may also determine whether the data is cold in determining whether to remove the data from the cache device. The cache device may present to clients a logical space that is the same size as the backing store. The cache device may be transparent to the clients.

Apparatus, system, and method for caching data on a solid-state storage device

An apparatus, system, and method are disclosed for allocating non-volatile storage. The storage device may present a logical address, which may exceed a physical storage capacity of the device. The storage device may allocate logical capacity in the logical address space. An allocation request may be allowed when there is sufficient unassigned and/or unallocated logical capacity to satisfy the request. Data may be stored on the non-volatile storage device by requesting physical storage capacity. A physical storage request, such as a storage request or physical storage reservation, when there is sufficient available physical storage capacity to satisfy the request. The device may maintain an index to associate logical identifiers (LIDs) in the logical address space with storage locations on the storage device. This index may be used to make logical capacity allocations and/or to manage physical storage space.

Apparatus, system, and method for allocating storage

In a method of writing data to a file system on a solid state drive, a file stream is opened for writing to a file in the file system. A life expectancy value predicting a length of time the data to be written will be stored in the file system is attached to the file stream. The data is written to the file stream and stored on the solid state storage device according to the life expectancy value attached to the data. In one embodiment, a unique identifier may be used as the life expectancy value for writing a group of related files predicted to be stored in the file system for substantially the same length of time. The life expectancy value may be predicted based on a file type of the file being written. The life expectancy value may be stored as metadata for the file being written.

Pre-organization of data

Memory mapping techniques for non-volatile memory are disclosed where logical sectors are mapped into physical pages using data structures in volatile and non-volatile memory. In some implementations, a first lookup table in non-volatile memory maps logical sectors directly into physical pages. A second lookup table in volatile memory holds the location of the first lookup table in non-volatile memory. An index cache tree in volatile memory holds the physical addresses of the most recently written or accessed logical sectors in a compressed format.

Index cache tree

Systems and methods are disclosed for efficient buffering for a system having non-volatile memory (“NVM”). In some embodiments, a control circuitry of a system can use heuristics to determine whether to perform buffering of one or more write commands received from a file system. In other embodiments, the control circuitry can minimize read energy and buffering overhead by efficiently re-ordering write commands in a queue along page-aligned boundaries of a buffer. In further embodiments, the control circuitry can optimally combine write commands from a buffer with write commands from a queue. After combining the commands, the control circuitry can dispatch the commands in a single transaction.

Efficient buffering for a system having non-volatile memory

Systems and methods are disclosed for managing a non-volatile memory (“NVM”), such as a flash memory. To prevent data errors due to leakage effects, the NVM may be refreshed. For example, a reserved portion of the NVM may be selected, and a predetermined pattern can be stored into the reserved portion. The reserved portion can then be monitored for storage deterioration over time. After determining that storage deterioration of the reserved portion has occurred, the NVM can be refreshed. In some embodiments, a controller can attempt to distinguish data errors due to leakage effects from data errors due to disturb issues.

Systems and methods for refreshing non-volatile memory

Systems and methods are provided for performing incremental garbage collection for non-volatile memories (“NVMs”), such as flash memory. In some embodiments, an electronic device including the NVM may perform incremental garbage collection to free up and erase a programmed block of the NVM. The programmed block may include valid data and invalid data, and the electronic device may be configured to copy the valid data from the programmed block to an erased block in portions. In between programming each portion of the valid data to the erased block, the electronic device can program host data to the erased block. This way, the electronic device can stagger the garbage collection operations and prevent a user from having to experience one long garbage collection operation.

Daniel J. Post

Papers

Pre-organization of data

Index cache tree

Efficient buffering for a system having non-volatile memory

Systems and methods for refreshing non-volatile memory

Incremental garbage collection for non-volatile memories