Most activated memory portion handling

摘要

Activation of portions of a memory is tracked to allow an affected portion of the memory to be refreshed before it is corrupted by multiple activations. An address for the accessed portion of memory, called the aggressor row, is compared to addresses stored in a content addressable memory (CAM). If the address is not already stored in the CAM, it is stored, casting out another address if necessary, and a count based on an Others value is stored in the CAM with the address. If the address is already stored in the CAM, its associated count is incremented. If a count associated with an address exceeds a threshold based on a maximum activation count, another portion of memory, such as a victim row of memory adjacent to the aggressor row of memory, is refreshed, and the count reset.

主权项

1. An apparatus for activation tracking comprising:
calculating logic configured to determine a number of times that a portion of a memory has been accessed; storage memory, coupled to the calculating logic, configured to store the number of times that the portion of a memory has been accessed as well as an address for the portion, wherein the number of times and the address are cast out in response to where sufficient other portions have been accessed more times; an others register configured to store a value representing a maximum number of times that any address which is not stored in the storage memory has been accessed; threshold logic, coupled to the calculating logic, configured to determine that the number of times that the portion is accessed exceeds a certain threshold; and marking logic, coupled to the calculating logic, configured to define that a second portion of the memory needs refresh, based on the number of times exceeding the certain threshold.