A method of managing a garbage collection (GC) operation on a flash memory includes: setting a GC starting threshold, wherein the GC starting threshold indicates a predetermined spare block number that is higher than a target spare block number of spare blocks maintained by a flash translation layer (FTL) of the flash memory; determining whether to start the GC operation according to a current number of spare blocks in the flash memory and the GC starting threshold; and performing the GC operation on a source block in the flash memory when the current number of spare blocks is lower than or equal to the GC starting threshold.

A processing device in a memory system identifies, while the memory device is in a first state condition, a plurality of workload conditions associated with the memory device, wherein the plurality of workload conditions comprise data reflecting a performance condition of the memory device. The processing device determines, while the memory device is in the first state condition, a host rate of a host system write performance for the memory device based on one or more workload conditions of the plurality of workload conditions. The processing device determines that one or more workload conditions of the plurality of workload conditions satisfies a first threshold criterion. Responsive to determining that the one or more workload conditions of the plurality of workload conditions satisfies the first threshold criterion, the processing device detects a change in a condition of the memory device from the first state to a second state. The processing device determines, while the memory device is in the second state condition, an adjusted host rate based on the host rate and a calculated adjustment value. The processing device uses the adjusted host rate to determine a credit consuming rate for a host write operation for the memory device.

Systems, apparatuses, and methods related to media management, including “garbage collection,” in memory or storage systems or sub-systems, such as solid state drives, are described. For example, a criticality value can be determined and used as a basis for managing a garbage collection operation on a data block. A controller or the system or sub-system may determine that a criticality value associated with performing a garbage collection operation satisfies a condition. Based on determining that the condition is satisfied, a parameter associated with performing the garbage collection operation can be adjusted. The garbage collection operation is performed on the data block stored on the memory component using the adjusted parameter.

Method and apparatus for managing data in a storage device, such as a solid-state drive (SSD). In some embodiments, a main memory has memory cells arranged on dies arranged as die sets accessible using parallel channels. A controller is configured to arbitrate resources required by access commands to transfer data to or from the main memory using the parallel channels, to monitor an occurrence rate of collisions between commands requiring an overlapping set of the resources, and to adjust a ratio among different types of commands executed by the controller responsive to the occurrence rate of the collisions. In further embodiments, the controller may divide a full command into multiple partial commands, each of which are executed as the associated system resources become available. In some cases, the ratio is established between read commands and write commands issued to the main memory.

Method and apparatus for managing data in a storage device, such as a solid-state drive (SSD). A non-volatile memory (NVM) is arranged into multiple garbage collection units (GCUs) each separately erasable and allocatable as a unit. Read circuitry applies read voltages to memory cells in the GCUs to sense a programmed state of the memory cells. Calibration circuitry groups different memory cells from different GCUs into calibration groups that share a selected set of read voltages. A read command queue accumulates pending read commands to transfer data from the NVM to a local read buffer. Read command coalescing circuitry coalesces selected read commands from the queue into a combined command for execution as a single batch command. The combined batch command may include read voltages for use in retrieval of the requested data.

An operating method of a memory controller configured to control a memory device including memory blocks each for storing a plurality of pages is provided. The operating method includes transferring a program command to the memory device based on a write request from a host, updating a valid page bitmap representing validity of a plurality of pages based on valid page information received from the memory device, calculating a fragmentation ratio representing a segmentation degree between at least one valid page and at least one invalid page of a memory block based on the valid page bitmap, determining source blocks among the memory blocks in ascending order of fragmentation ratios, and performing garbage collection on the source blocks.

A non-volatile memory includes a plurality of physical blocks each including a respective plurality of cells, where each cell is individually capable of storing multiple bits of data. A controller for the non-volatile memory maintains dynamically resizable pools of physical blocks, including at least a low-density pool of physical blocks in which cells are configured to store a fewer number of bits and a high-density pool of physical blocks in which cells are configured to store a greater number of bits. The controller detects an imbalance in utilization between the low-density and high-density pools and, based on detection of the pool imbalance, restricts data placement in the low-density pool, enables garbage collection from the low-density pool back into the low-density pool to compact the low-density pool, and re-enables data placement to the low-density pool based on availability of a threshold number of free physical blocks in the low-density pool.

A method and apparatus for performing access control of a memory device with aid of additional physical address information are provided. The method includes: during a garbage collection procedure, reading valid data from a source block and writing the valid data into a destination block; updating at least one logical-to-physical address mapping table; receiving a first read request from a host device, wherein the first read request indicates reading at a first logical address; in response to the first read request, reading the valid data of the destination block according to the second physical address associated with the first logical address; receiving a second read request from the host device, wherein the second read request indicates reading at the first logical address; and in response to the second read request, reading the valid data of the source block according to the first physical address associated with the first logical address.

A method for managing memory leaks in a memory device includes grouping, by a garbage collection system, a plurality of similar memory allocations of the memory device into one or more Unique Fixed Identifiers (UFIs); identifying, by the garbage collection system, one of the one or more UFIs having a highest accumulated memory size and adding each of the plurality of memory allocations in the identified one of the one or more UFIs into a Potential Leak Candidate List (PLCL); identifying, by the garbage collection system, the memory leaks in the memory device by identifying unreferenced memory addresses associated with the plurality of memory allocations in the PLCL; and releasing, by the garbage collection system, the identified unreferenced memory addresses associated with the plurality of memory allocations corresponding to the memory leaks into the memory device.

Memory devices and methods of operating memory devices in which maintenance operations can be scheduled on an as-needed basis for those memory portions where activity (e.g., operations in excess of a predetermined threshold) warrants a maintenance operation are disclosed. In one embodiment, an apparatus comprises a memory including a memory location, and circuitry configured to determine a count corresponding to a number of operations at the memory location, to schedule a maintenance operation for the memory location in response to the count exceeding a first predetermined threshold, and to decrease the count by an amount corresponding to the first predetermined threshold in response to executing the scheduled maintenance operation. The circuitry may be further configured to disallow, in response to determining that the count has reached a maximum permitted value, further operations at the memory location until after the count has been decreased.