Disclosed are examples of a system and method to communicate cache line eviction data from a CPU subsystem to a home node over a prioritized channel and to release the cache subsystem early to process other transactions.

Techniques for maintaining cache coherency comprising storing data blocks associated with a main process in a cache line of a main cache memory, storing a first local copy of the data blocks in a first local cache memory of a first processor, storing a second local copy of the set of data blocks in a second local cache memory of a second processor executing a first child process of the main process to generate first output data, writing the first output data to the first data block of the first local copy as a write through, writing the first output data to the first data block of the main cache memory as a part of the write through, transmitting an invalidate request to the second local cache memory, marking the second local copy of the set of data blocks as delayed, and transmitting an acknowledgment to the invalidate request.

An apparatus includes a CPU core and a L1 cache subsystem including a L1 main cache, a L1 victim cache, and a L1 controller. The apparatus includes a L2 cache subsystem including a L2 main cache, a shadow L1 main cache, a shadow L1 victim cache, and a L2 controller configured to receive a read request from the L1 controller as a single transaction. Read request includes a read address, a first indication of an address and a coherence state of a cache line A to be moved from the L1 main cache to the L1 victim cache to allocate space for data returned in response to the read request, and a second indication of an address and a coherence state of a cache line B to be removed from the L1 victim cache in response to the cache line A being moved to the L1 victim cache.

Techniques including receiving configuration information for a trigger control channel of the one or more trigger control channels, the configuration information defining a first one or more triggering events, receiving a first memory management command, store the first memory management command, detecting a first one or more triggering events, and triggering the stored first memory management command based on the detected first one or more triggering events.

A method for improving cache hit ratios for selected volumes within a storage system is disclosed. In one embodiment, such a method includes monitoring I/O to multiple volumes residing on a storage system. The storage system includes a cache to store data associated with the volumes. The method determines, from the I/O, which particular volumes of the multiple volumes would benefit the most if provided favored status in the cache. The favored status provides increased residency time in the cache to the particular volumes compared to volumes not having the favored status. The method generates a list of the particular volumes and transmits the list to the storage system. The storage system, in turn, provides increased residency time to the particular volumes in accordance with their favored status. A corresponding system and computer program product are also disclosed.

A cache memory includes a data array, a directory of contents of the data array that specifies coherence state information, and snoop logic that processes operations snooped from a system fabric by reference to the data array and the directory. The snoop logic, responsive to snooping on the system fabric a request of a flush or clean memory access operation of an initiating coherence participant, determines whether the directory indicates the cache memory has coherence ownership of a target address of the request. Based on determining the directory indicates the cache memory has coherence ownership of the target address, the snoop logic provides a coherence response to the request that causes coherence ownership of the target address to be transferred to the initiating coherence participant, such that the initiating coherence participant can protect the target address against conflicting requests.

A cache memory includes a data array, a directory of contents of the data array that specifies coherence state information, and snoop logic that processes operations snooped from a system fabric by reference to the data array and the directory. The snoop logic, responsive to snooping on the system fabric a request of a first flush/clean memory access operation that specifies a target address, determines whether or not the cache memory has coherence ownership of the target address. Based on determining the cache memory has coherence ownership of the target address, the snoop logic services the request and thereafter enters a referee mode. While in the referee mode, the snoop logic protects a memory block identified by the target address against conflicting memory access requests by the plurality of processor cores until conclusion of a second flush/clean memory access operation that specifies the target address.

Techniques for accessing memory by a memory controller, comprising receiving, by the memory controller, a memory management command to perform a memory management operation at a virtual memory address, translating the virtual memory address to a physical memory address, wherein the physical memory address comprises an address within a cache memory, and outputting an instruction to the cache memory based on the memory management command and the physical memory address.

An apparatus includes a CPU core and a L1 cache subsystem including a L1 main cache, a L1 victim cache, and a L1 controller. The apparatus includes a L2 cache subsystem including a L2 main cache, a shadow L1 main cache, a shadow L1 victim cache, and a L2 controller configured to receive a read request from the L1 controller as a single transaction. Read request includes a read address, a first indication of an address and a coherence state of a cache line A to be moved from the L1 main cache to the L1 victim cache to allocate space for data returned in response to the read request, and a second indication of an address and a coherence state of a cache line B to be removed from the L1 victim cache in response to the cache line A being moved to the L1 victim cache.

A system for computing. In some embodiments, the system includes: a memory, the memory including one or more function-in-memory circuits; and a cache coherent protocol interface circuit having a first interface and a second interface. A function-in-memory circuit of the one or more function-in-memory circuits may be configured to perform an operation on operands including a first operand retrieved from the memory, to form a result. The first interface of the cache coherent protocol interface circuit may be connected to the memory, and the second interface of the cache coherent protocol interface circuit may be configured as a cache coherent protocol interface on a bus interface.