Systems and methods are provided for using a distributed cache architecture with different methods to load balance requests depending upon whether a requested data item is a freely-requested item (e.g., a “hot key”). The cache may be implemented as a consistent hash ring, and most keys may be assigned to particular node based on a consistent hash. For hot key requests, the requests may be distributed among a subset of nodes rather than being assigned to a specific node using consistent hashing. When a witness service is used to ensure that cached data is fresh, verification requests for data regarding hot keys may be batched to avoid overloading the witness service with hot key requests.

A system for managing virtual memory. The system includes a first processing unit configured to execute a first operation that references a first virtual memory address. The system also includes a first memory management unit (MMU) associated with the first processing unit and configured to generate a first page fault upon determining that a first page table that is stored in a first memory unit associated with the first processing unit does not include a mapping corresponding to the first virtual memory address. The system further includes a first copy engine associated with the first processing unit. The first copy engine is configured to read a first command queue to determine a first mapping that corresponds to the first virtual memory address and is included in a first page state directory. The first copy engine is also configured to update the first page table to include the first mapping.

A system for managing virtual memory. The system includes a first processing unit configured to execute a first operation that references a first virtual memory address. The system also includes a first memory management unit (MMU) associated with the first processing unit and configured to generate a first page fault upon determining that a first page table that is stored in a first memory unit associated with the first processing unit does not include a mapping corresponding to the first virtual memory address. The system further includes a first copy engine associated with the first processing unit. The first copy engine is configured to read a first command queue to determine a first mapping that corresponds to the first virtual memory address and is included in a first page state directory. The first copy engine is also configured to update the first page table to include the first mapping.

A memory management method includes determining a memory page that needs to be swapped out of a memory, for each memory page that needs to be swapped out, generating, based on the memory page, a work task reclaiming the memory page, and allocating each work task to a dedicated worker thread for execution.

A memory management method includes determining a memory page that needs to be swapped out of a memory, for each memory page that needs to be swapped out, generating, based on the memory page, a work task reclaiming the memory page, and allocating each work task to a dedicated worker thread for execution.

A heterogeneous memory system is implemented using a low-latency near memory (NM) and a high-latency far memory (FM). Pages in the memory system include NM blocks stored in the NM and FM blocks stored in the FM. A page is assigned to a region in the memory system based on the proportion of NM blocks in the page. When accessing a block, the block address is used to determine a region of the memory system, and a block offset is used to determine whether the block is stored in NM or FM. The memory system may observe memory accesses to determine the access statistics of the page and the block. Based on a page's hotness and access density, the page may be migrated to a different region. Based on a block's hotness, the block may be migrated between NM and FM allocated to the page.

A heterogeneous memory system is implemented using a low-latency near memory (NM) and a high-latency far memory (FM). Pages in the memory system include NM blocks stored in the NM and FM blocks stored in the FM. A page is assigned to a region in the memory system based on the proportion of NM blocks in the page. When accessing a block, the block address is used to determine a region of the memory system, and a block offset is used to determine whether the block is stored in NM or FM. The memory system may observe memory accesses to determine the access statistics of the page and the block. Based on a page's hotness and access density, the page may be migrated to a different region. Based on a block's hotness, the block may be migrated between NM and FM allocated to the page.

A system comprises a processor coupled to a plurality of memory units. Each of the plurality of memory units includes a request processing unit and a plurality of memory banks. Each request processing unit includes a plurality of decomposition units and a crossbar switch, the crossbar switch communicatively connecting each of the plurality of decomposition units to each of the plurality of memory banks. The processor includes a plurality of processing elements and a communication network communicatively connecting the plurality of processing elements to the plurality of memory units. At least a first processing element of the plurality of processing elements includes a control logic unit and a matrix compute engine. The control logic unit is configured to access the plurality of memory units using a dynamically programmable distribution scheme.

Techniques for implementing user-space remote memory paging are provided. In one set of embodiments, these techniques include a user-space remote memory paging (RMP) runtime that can: (1) pre-allocate one or more regions of remote memory for use by an application; (2) at a time of receiving/intercepting a memory allocation function call invoked by the application, map the virtual memory address range of the allocated local memory to a portion of the pre-allocated remote memory; (3) at a time of detecting a page fault directed to a page that is mapped to remote memory, retrieve the page via Remote Direct Memory Access (RDMA) from its remote memory location and store the retrieved page in a local main memory cache; and (4) on a periodic basis, identify pages in the local main memory cache that are candidates for eviction and write out the identified pages via RDMA to their mapped remote memory locations if they have been modified.

Memory controllers, devices, modules, systems and associated methods are disclosed. In one embodiment, a memory system is disclosed. The memory system includes volatile memory configured as a cache. The cache stores first data at first storage locations. Backing storage media couples to the cache. The backing storage media stores second data in second storage locations corresponding to the first data. Logic uses a presence or status of first data in the first storage locations to cease maintenance operations to the stored second data in the second storage locations.