Abstract: The present disclosure includes apparatuses and methods for performing data restore operations in memory. An embodiment includes a memory, and a controller configured to perform a data restore operation on data stored in the memory using a first table and a second table stored in the controller, wherein the first table includes a current mapping of the data stored in the memory that is based on a previous assessment of previous error rates associated with the data stored in the memory, and the second table includes a new mapping of the data stored in the memory that is based on a current assessment of current error rates associated with the data stored in the memory.

Abstract: A memory device having a memory array with a plurality of memory addresses and a controller operably coupled to the memory array is described. The controller is configured to store a sketch comprising d rows and w columns, wherein d and w are positive integers. Each of the d rows corresponds to a different one of d hash functions. The controller is also configured to detect an event associated with a first memory address of the plurality of memory addresses and to hash the first memory address with each of the d hash functions to generate a corresponding d sketch locations. The controller is further configured to adjust, for each of the d sketch locations, a stored sketch value by a first amount corresponding to the event.

Abstract: A memory device having a memory array and a controller operably coupled to the memory array is described. The controller is configured to store a sketch comprising d rows and w columns, wherein d and w are positive integers. Each row corresponds to a different one of d hash functions. The controller is also configured to detect an event associated with a memory address and to hash the memory address with each of the d hash functions to generate a corresponding d sketch locations. The controller is further configured, for each of the d sketch locations, to set a detection window flag, if it is not already set, and to adjust a stored sketch value by an amount corresponding to the event. The controller is also configured to evaluate a summary metric corresponding to the stored sketch value in each of the d sketch locations to determine if a threshold value has been reached.

Abstract: A memory device can include three-dimensional memory entities each including a plurality of two-dimensional memory entities. A controller can read data from the memory at a first resolution and collect error rate information from the memory at a second resolution including a portion of a two-dimensional memory entity. The controller can determine a quantity of two-dimensional memory entities that have a greater error rate than a remainder of the two-dimensional memory entities based on the error rate information. The controller can determine a quantity of portions of three-dimensional memory entities that have a greater error rate than a remainder of the portions of three-dimensional memory entities based on the error rate information excluding error rate information for portions of the two-dimensional memory entities associated with the quantity of two-dimensional memory entities.