Abstract: Methods, systems, and devices for performing data migration operations using a memory system are described. The memory system may include a data migration component, such as a driver, for facilitating the transfer of data between a first memory device that may implement a first memory technology (e.g., having a relatively fast access speed) and a second memory device that may implement a second memory technology (e.g., having a relatively large capacity). The component may indicate the data migration operation to a second component (e.g., a controller) of the memory system. The second component may initiate the transfer of data between the first memory device and the second memory device based on the receiving the indication of the data migration operation. In some cases, the transfer of data between the first memory device and the second memory device may occur within the memory system without being transferred through a host device.

Abstract: A method includes determining a traffic pattern of access requests within a queue or a system, or both and dynamically adjusting, within a particular range, a queue depth of the queue based on the determined traffic pattern of access requests to balance bandwidth and latency associated with executing the access requests.

Abstract: The present disclosure includes apparatuses and methods related to transaction identification. An example apparatus can determine a transaction identification (TID) associated with a command by comparing a host transaction identification (TID) record with a memory device transaction identification (TID) record.

Abstract: The present disclosure includes apparatuses and methods related to a non-deterministic memory protocol. An example apparatus can perform operations on the memory device based on commands received from a host according to a protocol, wherein the protocol includes non-deterministic timing of the operations. The memory device can be a non-volatile dual in-line memory module (NVDIMM) device.

Abstract: A method includes allocating, via a tier allocation component, a first portion of data to a first tier memory component and writing the first portion of data to the first tier memory component in response to a first tier free list having an available entry. The method further includes evicting a second portion of data from the first tier memory component in response to the first tier free list being empty when the first portion of data is allocated to the first tier memory component and writing the first portion of data to the first tier memory component in response to evicting the second portion of data.

Abstract: An energy-efficient and area-efficient, mitigation of errors in a memory media device that are caused by row hammer attacks and the like is described. The detection of errors is deterministically performed while maintaining, in an SRAM, a number of row access counters that is smaller than the total number of rows protected in the memory media device. The reduction of the number of required counters is achieved by aliasing a plurality of rows that are being protected to each counter. The mitigation may be implemented on a per-bank basis, per-channel basis or per-memory media device basis. The memory media device may be DRAM.

Abstract: Systems and methods for area-efficient mitigation of errors that are caused by row hammer attacks and the like in a memory media device are described. The counters for counting row accesses are maintained in a content addressable memory (CAM) the provides fast access times. The detection of errors is deterministically performed while maintaining a number of row access counters that is smaller than the total number of rows protected in the memory media device. The circuitry for the detection and mitigation may be in the memory media device or in a memory controller to which the memory media device attaches. The memory media device may be dynamic random access memory (DRAM).

Abstract: Apparatuses and methods for performing data migration operations are disclosed. An apparatus may include at least two interfaces, a first interface supporting data migration operations and a second interface supporting access operations associated with a host device. In some cases, the access operations may be a signal or protocol according to an industry standard or specification (e.g., a DRAM interface specification). The second interface may facilitate supporting industry standard applications, while the first interface supporting data migration operations may provide improved bandwidth for migrating data within the apparatus. The apparatus may include a buffer coupled with the interface and a bank cluster including two or more banks of memory cells. When a host device addresses a bank of the bank cluster, the apparatus may perform one or more data migration operations using the buffer and a different bank of the bank cluster.

Abstract: The present disclosure includes apparatuses and methods related to a memory controller, such as a host memory controller. An example apparatus can include a host memory controller coupled to a first memory device and a second memory device via a channel, wherein the host memory controller is configured to send a first number of commands to the first memory device using a first device select signal, and send a second number of commands to the second memory device using a second device select signal.

Abstract: Data is stored at a cache portion of a cache memory of a memory sub-system responsive to a request to perform a write operation to write the data. A duplicate copy of the data is stored at a write buffer portion of the cache memory. The cache memory is partitioned into the cache portion and the write buffer portion. An entry that maps a location of the duplicate copy of the data stored at the write buffer portion of the cache memory to a location of the data stored at the cache portion of the cache memory is recorded in a write buffer record.

Abstract: A method includes receiving, at a direct memory access (DMA) controller of a memory device, a first command from a first cache controller coupled to the memory device to prefetch first data from the memory device and sending the prefetched first data, in response to receiving the first command, to a second cache controller coupled to the memory device. The method can further include receiving a second command from a second cache controller coupled to the memory device to prefetch second data from the memory device, and sending the prefetched second data, in response to receiving the second command, to a third cache controller coupled to the memory device.

Abstract: The present disclosure includes apparatuses and methods related to memory module interfaces. A memory module, which may include volatile memory or nonvolatile memory, or both, may be configured to communicate with a host device via one interface and to communicate with another memory module using a different interface. Memory modules may thus be added or removed from a system without impacting a PCB-based bus to the host, and memory modules may communicate with one another without accessing a bus to the host. The host interface may be configured according to one protocol or standard, and other interfaces between memory modules may be configured according to other protocols or standards.

Abstract: An apparatus includes circuitry couplable to a host system and a memory device. The circuitry is configured to determine whether a page table maintained on the circuitry includes a physical address of the memory device corresponding to a virtual address associated with a TLB fill request from the host system. Responsive to determining that the page table includes the physical address, the circuitry provides signaling indicative of a completion to the TLB fill request to the host system, prefetch a page of data at the physical address from the memory device using the physical address from the page table, and provide signaling indicative of the page of data to the host system.

Abstract: An indication to perform an eviction operation on a cache line in a cache can be received. A determination can be made as to whether at least one sector of the cache line is associated with invalid data. In response to determining that at least one sector of the cache line is associated with invalid data, a read operation can be performed to retrieve valid data associated with the at least one sector. The at least one sector of the cache line that is associated with the invalid data can be modified based on the valid data. Furthermore, the eviction operation can be performed on the cache line with the modified at least one sector.

Abstract: A method comprising receiving a memory access request comprising an address of data to be accessed and determining an access granularity of the data to be accessed based on the address of the data to be accessed. The method further includes, in response to determining that the data to be accessed has a first access granularity, generating first cache line metadata associated with the first access granularity and in response to determining that the data to be accessed has a second access granularity, generating second cache line metadata associated with the second access granularity. The method further includes storing the first cache line metadata and the second cache line metadata in a single cache memory component.

Abstract: A system includes a first controller configured to adjust a count of a number of first transactions and adjust a count of a number of second transactions. The count of the number of first transactions and the count of the number of second transactions are adjusted when a first transaction or second transaction is either received or executed by a second controller. The second controller is coupled to the first controller and is configured to limit the number of first transactions to a particular quantity of outstanding first transactions, limit the number of second transactions to a particular quantity of outstanding second transactions, and limit a number of total transactions to a particular quantity of outstanding total transactions.

Abstract: Exemplary methods, apparatuses, and systems include detecting an operation to write dirty data to a cache. The cache is divided into a plurality of channels. In response to the operation, the dirty data is written to a first cache line in the cache, the first cache line being accessed via a first channel. Additionally, a redundant copy of the dirty data is written to a second cache line in the cache. The second cache line serves as a redundant write buffer and is accessed via a second channel, the first and second channels differing from one another. A metadata entry for the second cache line is updated to reference a location of the dirty data in the first cache line.

Abstract: A method includes, responsive to a SET command associated with a key-value store, concurrently updating the key-value store maintained on a non-persistent memory device of a memory sub-system and a mirror of the key-value store maintained on a persistent memory device of the memory sub-system. The method further includes responsive to a GET command associated with the key-value store, retrieving a value of a key from the key-value store maintained on the non-persistent memory device.

Abstract: A method includes receiving, at a direct memory access (DMA) controller of a memory device, a first command from a first cache controller coupled to the memory device to prefetch first data from the memory device and sending the prefetched first data, in response to receiving the first command, to a second cache controller coupled to the memory device. The method can further include receiving a second command from a second cache controller coupled to the memory device to prefetch second data from the memory device, and sending the prefetched second data, in response to receiving the second command, to a third cache controller coupled to the memory device.

Abstract: Exemplary methods, apparatuses, and systems include identifying that a first cache line from a first cache is subject to an operation that copies data from the first cache to a non-volatile memory. A first portion of the first cache line stores clean data and a second portion of the first cache line stores dirty data. A redundant copy of the dirty data is stored in a second cache line of the first cache. In response to identifying that the first cache line is subject to the operation, metadata associated with the redundant copy of the dirty data is used to copy the dirty data to a non-volatile memory while omitting the clean data.