Abstract: A system and method of managing the storage of data is described where a plurality of requesting entities can be permitted access to a shared data resource. When a modification to the data is needed, the request may be executed as an atomic operation. To do this the memory region is temporarily locked until the atomic operation is completed so that other operations related to the data are deferred until the atomic operation has completed. The lock is secured by reference to a data array or register of fixed length where the address of the locked data region is represented by a bit, the position of which is determined by computing a hash value of the address modulo the length of the lock register.

Abstract: A memory system is described, where a plurality of memory modules is connected to a memory controller. The power status of each of the memory modules is controlled, depending on the functions being performed by the memory module. When no read or write operation is being performed on a particular memory module, at least a portion of the circuitry may be operated in a lower power mode. A memory circuit associated with the memory module may be placed in a low power mode by disabling a clock. The memory circuit data integrity may be secured by issuing refresh commands while when the memory circuit is in the lower power mode, by enabling the clock, issuing the refresh command, and disabling the clock after completion of the refresh operation.

Abstract: A system and method for managing the storage of data in non-volatile memory is described. In an aspect, the data may be described by metadata and a transaction log file that are checkpointed from a volatile memory into the non-volatile memory. Actions that take place between the last checkpointing of a metadata segment and log file segment are discovered by scanning the non-volatile memory blocks, taking account of a record of the highest sector in each block that is known to have been recorded. Any later transactions are discovered and used to update the recovered metadata so that the metadata correctly represents the stored data.

Abstract: A system and method of managing the storage of data in flash memory performs snapshots of the data by maintaining the data at the epoch that the snapshot is performed in the same physical memory location. Data that is modified after the snapshot is then stored to a new physical memory location and referenced to the snapshot location. When a user read operation is performed, the data is read from the original location if the read operation is for the snapshot data. The read operation for dynamic data is performed from the original location if the data has not change since the snapshot epoch, or from the referenced data location if the data has changed since the snapshot epoch. Snapshots are released by dereferencing the original location if the data has been changed since the snapshot epoch.