A data access system including a processor and a storage system including a main memory and a cache module. The cache module includes a FLC controller and a cache. The cache is configured as a FLC to be accessed prior to accessing the main memory. The processor is coupled to levels of cache separate from the FLC. The processor generates, in response to data required by the processor not being in the levels of cache, a physical address corresponding to a physical location in the storage system. The FLC controller generates a virtual address based on the physical address. The virtual address corresponds to a physical location within the FLC or the main memory. The cache module causes, in response to the virtual address not corresponding to the physical location within the FLC, the data required by the processor to be retrieved from the main memory.

A memory system includes a volatile first storing unit, a nonvolatile second storing unit in which data is managed in a predetermined unit, and a controller that writes data requested by a host apparatus in the second storing unit via the first storing unit and reads out data requested by the host apparatus from the second storing unit to the first storing unit and transfers the data to the host apparatus. The controller includes a management table for managing the number of failure areas in a predetermined unit that occur in the second storing unit and switches, according to the number of failure areas, an operation mode in writing data in the second storing unit from the host apparatus.

Activation rates of memory locations associated with memory addresses are monitored. The activation rates of the memory locations associated with the memory addresses are regulated. The regulating of the activation rates of the memory locations associated with the memory addresses includes selectively updating a cache with the memory addresses based on the activation rates.

Systems and methods are provided for expanding the available memory of a storage controller. The systems and methods utilize a PCIe memory controller connected to the backend interface of the storage controller. Memory of the PCIe memory controller is memory mapped to controller memory of the storage controller. The PCIe connection allows the storage controller to access the memory of the PCIe memory controller with latencies similar to that of the controller memory.

An apparatus is described that includes memory controller logic circuitry to interface with a memory side cache of a multi-level system memory. The memory controller logic circuitry includes error tracking circuitry to track errors of cache line slots in the memory side cache. The memory controller logic circuitry also comprises faulty list circuitry to store identifiers of faulty cache line slots that are deemed to be excessively error prone. The memory controller logic circuitry is to declare a miss in the memory side cache for requests that map to cache line slots identified in the faulty list.

The present invention provides a DRAM/NVM hierarchical heterogeneous memory system with software-hardware cooperative management schemes. In the system, NVM is used as large-capacity main memory, and DRAM is used as a cache to the NVM. Some reserved bits in the data structure of TLB and last-level page table are employed effectively to eliminate hardware costs in the conventional hardware-managed hierarchical memory architecture. The cache management in such a heterogeneous memory system is pushed to the software level. Moreover, the invention is able to reduce memory access latency in case of last-level cache misses. Considering that many applications have relatively poor data locality in big data application environments, the conventional demand-based data fetching policy for DRAM cache can aggravates cache pollution. In the present invention, an utility-based data fetching mechanism is adopted in the DRAM/NVM hierarchical memory system, and it determines whether data in the NVM should be cached in the DRAM according to current DRAM memory utilization and application memory access patterns. It improves the efficiency of the DRAM cache and bandwidth usage between the NVM main memory and the DRAM cache.

Systems, methods and/or devices are used to perform memory-efficient mapping of block/object addresses. In one aspect, a method of managing a storage system having one or more storage devices includes a tiered data structure in which each node has a logical ID and entries in the nodes reference other nodes in the tiered data structure using the logical IDs. As a result, when a child node is updated and stored to a new location, but retains its logical ID, its parent node does not need to be updated, because the logical ID in the entry referencing the child node remains unchanged. Further, the storage system uses a secondary mapping table to translate the logical IDs to the corresponding physical locations of the corresponding nodes. Additionally, the secondary mapping table is cached in volatile memory, and as a result, the physical location of a required node is determined without accessing non-volatile memory.

A read method executed by a computing system includes a processor, at least one nonvolatile memory, and at least one cache memory performing a cache function of the at least one nonvolatile memory. The method includes receiving a read request regarding a critical word from the processor. A determination is made whether a cache miss is generated, through a tag determination operation corresponding to the read request. Page data corresponding to the read request is received from the at least one nonvolatile memory in a wraparound scheme when a result of the tag determination operation indicates that the cache miss is generated. The critical word is output to the processor when the critical word of the page data is received.

Provided are a computer program product, system, and method for considering a frequency of access to groups of tracks and density of the groups to select groups of tracks to destage. One of a plurality of densities for one of a plurality of groups of tracks is incremented in response to determining at least one of that the group is not ready to destage and that one of the tracks in the group in the cache transitions to being ready to destage. A determination is made of a group frequency indicating a frequency at which tracks in the group are modified. At least one of the density and the group frequency is used for each of the groups to determine whether to destage the group. The tracks in the group in the cache are destaged to the storage in response to determining to destage the group.

A general matrix-matrix multiplication (GEMM) dataflow accelerator circuit is disclosed that includes a smart 3D stacking DRAM architecture. The accelerator circuit includes a memory bank, a peripheral lookup table stored in the memory bank, and a first vector buffer to store a first vector that is used as a row address into the lookup table. The circuit includes a second vector buffer to store a second vector that is used as a column address into the lookup table, and lookup table buffers to receive and store lookup table entries from the lookup table. The circuit further includes adders to sum the first product and a second product, and an output buffer to store the sum. The lookup table buffers determine a product of the first vector and the second vector without performing a multiply operation. The embodiments include a hierarchical lookup architecture to reduce latency. Accumulation results are propagated in a systolic manner.