The LLC (last-level cache) is the last, and
longest-latency, level in the memory hierarchy before main memory (DRAM). Any
memory requests missing here must be serviced by local or remote DRAM, with
significant latency. The LLC Miss metric shows a ratio of cycles with
outstanding LLC misses to all cycles.
A high number of CPU cycles is being spent waiting for LLC load misses
to be serviced. Possible optimizations are to reduce data working set size,
improve data access locality, blocking and consuming data in chunks that fit in
the LLC, or better exploit hardware prefetchers. Consider using software
prefetchers but they can increase latency by interfering with normal loads, and
can increase pressure on the memory system.