This metric represents percentage of elapsed time the system spent with high DRAM bandwidth utilization. Since this metric relies on the accurate peak system DRAM bandwidth measurement, explore the Bandwidth Utilization Histogram and make sure the Low/Medium/High utilization thresholds are correct for your system. You can manually adjust them, if required.
The system spent much time heavily utilizing DRAM bandwidth. Improve data accesses to reduce cacheline transfers from/to memory using these possible techniques: 1) consume all bytes of each cacheline before it is evicted (for example, reorder structure elements and split non-hot ones); 2) merge compute-limited and bandwidth-limited loops; 3) use NUMA optimizations on a multi-socket system. Note: software prefetches do not help a bandwidth-limited application. Run Memory Access analysis to identify data structures to be allocated in High Bandwidth Memory (HBM), if available.