Various embodiments mitigate busy time in a hierarchical store-through memory cache structure including a cache directory associated with a memory cache. The cache directory is divided into a plurality of portions each associated with a portion of memory cache. A determination is made that a first subpipe of a shared cache pipeline comprises a non-store request. The shared pipeline is communicatively coupled to the plurality of portions of the cache directory. A store command is prevented from being placed in a second subpipe of the shared cache pipeline based on determining that a first subpipe of the shared cache pipeline comprises a non-store request. Simultaneous cache lookup operations are supported between the plurality of portions of the cache directory and cache write operations. Two or more store commands simultaneously processed in a shared cache pipeline communicatively coupled to the plurality of portions of the cache directory.

Various embodiments mitigate busy time in a hierarchical store-through memory cache structure including a cache directory associated with a memory cache. The cache directory is divided into a plurality of portions each associated with a portion of memory cache. A determination is made that a first subpipe of a shared cache pipeline comprises a non-store request. The shared pipeline is communicatively coupled to the plurality of portions of the cache directory. A store command is prevented from being placed in a second subpipe of the shared cache pipeline based on determining that a first subpipe of the shared cache pipeline comprises a non-store request. Simultaneous cache lookup operations are supported between the plurality of portions of the cache directory and cache write operations. Two or more store commands simultaneously processed in a shared cache pipeline communicatively coupled to the plurality of portions of the cache directory.

Embodiments of the present disclosure generally relate to a target device handling overlap write commands. In one embodiment, a target device includes a non-volatile memory and a controller coupled to the non-volatile memory. The controller includes a random accumulated buffer, a sequential accumulated buffer, and an overlap accumulated buffer. The controller is configured to receive a new write command, classify the new write command, and write data associated with the new write command to one of the random accumulated buffer, the sequential accumulated buffer, or the overlap accumulated buffer. Once the overlap accumulated buffer becomes available, the controller first flushes to the non-volatile memory the data in the random accumulated buffer and the sequential accumulated buffer that was received prior in sequence to the data in the overlap accumulated buffer. The controller then flushes the available overlap accumulated buffer, ensuring that new write commands override prior write commands.

Embodiments of the present disclosure generally relate to a target device handling overlap write commands. In one embodiment, a target device includes a non-volatile memory and a controller coupled to the non-volatile memory. The controller includes a random accumulated buffer, a sequential accumulated buffer, and an overlap accumulated buffer. The controller is configured to receive a new write command, classify the new write command, and write data associated with the new write command to one of the random accumulated buffer, the sequential accumulated buffer, or the overlap accumulated buffer. Once the overlap accumulated buffer becomes available, the controller first flushes to the non-volatile memory the data in the random accumulated buffer and the sequential accumulated buffer that was received prior in sequence to the data in the overlap accumulated buffer. The controller then flushes the available overlap accumulated buffer, ensuring that new write commands override prior write commands.

Disclosed herein is an apparatus and method for controlling level 0 caches, capable of delivering data to a processor without errors and storing error-free data in the caches even when soft errors occur in the processor and caches. The apparatus includes: a level 0 cache #0 connected to the load/store unit of a first processor; a level 0 cache #1 connected to the load/store unit of a second processor; and a fault detection and recovery unit for reading from and writing to tag memory, data memory, and valid bit memory of the level 0 cache #0 and the level 0 cache #1, performing the write-back and flush of the level 0 cache #0 and the level 0 cache #1 based on information stored therein, and instructing the load/store units of the first and second processors to stall a pipeline and to restart an instruction #n.

Disclosed herein is an apparatus and method for controlling level 0 caches, capable of delivering data to a processor without errors and storing error-free data in the caches even when soft errors occur in the processor and caches. The apparatus includes: a level 0 cache #0 connected to the load/store unit of a first processor; a level 0 cache #1 connected to the load/store unit of a second processor; and a fault detection and recovery unit for reading from and writing to tag memory, data memory, and valid bit memory of the level 0 cache #0 and the level 0 cache #1, performing the write-back and flush of the level 0 cache #0 and the level 0 cache #1 based on information stored therein, and instructing the load/store units of the first and second processors to stall a pipeline and to restart an instruction #n.

In one embodiment, a processor includes a write combining buffer that includes a memory having a plurality of entries. The entries may be allocated to committed store operations transmitted by a load/store unit in the processor, and subsequent committed store operations may merge data with previous store memory operations in the buffer if the subsequent committed store operations are to addresses that match addresses of the previous committed store operations within a predefined granularity (e.g. the width of a cache port). The write combining buffer may be configured to retain up to N entries of committed store operations, but may also be configured to write one or more of the entries to the data cache responsive to receiving more than a threshold amount of non-merging committed store operations in the write combining buffer.

A system according to one embodiment includes non-volatile memory, and a non-volatile memory controller having a cache. An architecture of the cache supports separation of data streams, and the cache architecture supports parallel writes to different non-volatile memory channels. Additionally, the cache architecture supports pipelining of the parallel writes to different non-volatile memory planes. Furthermore, the non-volatile memory controller is configured to perform a direct memory lookup in the cache based on a physical block address. Other systems, methods, and computer program products are described in additional embodiments.

A system according to one embodiment includes non-volatile memory, and a non-volatile memory controller having a cache. An architecture of the cache supports separation of data streams, and the cache architecture supports parallel writes to different non-volatile memory channels. Additionally, the cache architecture supports pipelining of the parallel writes to different non-volatile memory planes. Furthermore, the non-volatile memory controller is configured to perform a direct memory lookup in the cache based on a physical block address. Other systems, methods, and computer program products are described in additional embodiments.

A cache memory includes: a tag storage section in which one of a plurality of indexes, each index containing a plurality of tag addresses and one suspension-indicating section, is looked up by a first address portion of an accessed address; a data storage section; a tag control section configured to, when the suspension-indicating section contained in the looked-up index indicates suspension, allow access relevant to the accessed address to wait, and when the suspension-indicating section contained in the looked-up index indicates non-suspension, compare a second address portion different from the first address portion of the accessed address to each of the plurality of tag addresses contained in the looked-up index, and detects a tag address matched with the second address portion; and a data control section.