Throttling support for row-hammer counters

A memory subsystem comprising:

• a memory controller coupled to the memory device, the memory controller to:
• monitor access to rows of a memory device for a timeframe, wherein the timeframe is divided into at least two sub-frames each having a respective predefined duration, and wherein the timeframe corresponds to a time period between two scheduled refresh commands;
• determine if a number of accesses for any of the rows during a first sub-frame of the at least two sub-frames exceeds a first threshold, the first threshold associated with risk of data corruption on a row physically adjacent to an accessed row;
• throttle accesses to the accessed row at a first rate if the number of accesses to the accessed row exceeds the first threshold and not throttle accesses to the accessed row at the first rate if the number of accesses to the accessed row does not exceed the first threshold;
• determine if a number of accesses for the accessed row during a second sub-frame of the at least two sub-frames exceeds a second threshold, wherein the second threshold is greater than the first threshold;
• throttle accesses to the accessed row at a second rate if the number of accesses to the accessed row exceeds the second threshold and not throttle accesses to the accessed row at the second rate if the number of accesses to the accessed row does not exceed the second threshold, wherein the second throttling rate is greater than the first throttling rate;
• and
• generate a targeted refresh with a refresh command, other than either of the two scheduled refresh commands, to refresh only the row physically adjacent to the accessed row in response to one of the number of accesses for the accessed row during the first sub-frame exceeding the first threshold and the number of accesses for the accessed row during the second sub-frame exceeding the second threshold.

An electronic device comprising:

• a memory subsystem having
• a memory device having multiple rows of memory, and
• a memory controller coupled to the memory device, the memory controller to:
• monitor access to rows of a memory device for a timeframe, wherein the timeframe is divided into at least two sub-frames each having a respective predefined duration, and wherein the timeframe corresponds to a time period between two scheduled refresh commands;
• determine if a number of accesses for any of the rows during a first sub-frame of the at least two sub-frames exceeds a first threshold, the first threshold associated with risk of data corruption on a row physically adjacent to an accessed row;
• throttle accesses to the accessed row at a first rate if the number of accesses to the accessed row exceeds the first threshold and not throttle accesses to the accessed row at the first rate if the number of accesses to the accessed row does not exceed the first threshold;
• determine if a number of accesses for the accessed row during a second sub-frame of the at least two sub-frames exceeds a second threshold, wherein the second threshold is greater than the first threshold, throttle accesses to the accessed row at a second rate if the number of accesses to the accessed row exceeds the second threshold and not throttle accesses to the accessed row at the second rate if the number of accesses to the accessed row does not exceed the second threshold, wherein the second throttling rate is greater than the first throttling rate;
• and
• generate a targeted refresh with a refresh command, other than either of the two scheduled refresh commands, to refresh only the row physically adjacent to the accessed row in response to one of the number of accesses for the accessed row during the first sub-frame exceeding the first threshold and the number of accesses for the accessed row during the second sub-frame exceeding the second threshold;
• and
• a multicore processor coupled with the memory subsystem to access the memory subsystem during execution.