Memory Controller Row Hammer Mitigation With Adaptive Responses

The patent implements dynamic row hammer mitigation by transitioning from static, one-size-fits-all protection strategies to adaptive responses that scale with threat intensity. The system monitors row hammer activity levels and dynamically adjusts mitigation responses, applying stronger protection only when necessary, thereby reducing unnecessary performance overhead during normal operation while maintaining data protection when threats are detected.

The patent changes the parameter of mitigation intensity from fixed to variable. By introducing multiple response levels (e.g., mild, moderate, severe mitigation) that correspond to different threat intensities, the system optimizes the balance between data protection and performance overhead. This allows the mitigation strength to be adjusted as a variable parameter based on actual row hammer activity rather than applying maximum protection constantly.

The patent applies partial mitigation action by implementing a scaled response system where only the necessary level of protection is applied at any given time. Instead of continuously applying maximum mitigation strength, the system applies partial protection (mild or moderate responses) during low or moderate threat levels, and only escalates to excessive action (severe mitigation) when row hammer activity reaches critical thresholds, thus optimizing the trade-off between protection and performance.

The patent implements periodic monitoring and evaluation of row hammer activity to determine appropriate mitigation levels. By continuously monitoring row activation patterns and periodically assessing threat intensity, the system can dynamically adjust mitigation responses in periodic cycles, applying strong protection only during periods when threats are detected and reducing or eliminating mitigation overhead during safe periods.

The patent segments the mitigation strategy into multiple distinct response levels (e.g., first, second, and third responses corresponding to mild, moderate, and severe mitigation). This segmentation allows the system to handle different threat levels with appropriately tailored responses, improving adaptability while maintaining relative implementation simplicity through a structured, tiered approach rather than a monolithic complex system.

The patent creates a universal mitigation framework that handles multiple threat levels through a single integrated system. The row hammer mitigation circuitry performs multiple functions by monitoring activity, determining threat levels, and selecting from various response options all within one unified structure, thereby achieving adaptability to varying threat levels without proportionally increasing implementation complexity.