L3 是 8 个物理核，16 个超线程共享，相当于单核 2MB，一块 CPU 有 8 个 L3，总共是256MB。
1 cat cpu0/cache/index3/shared_cpu_list 2 0-7,128-135 3 #cat cpu0/cache/index3/size 4 32768K 5 #cat cpu0/cache/index2/shared_cpu_list 6 0,128 7 #cat /sys/devices/system/cpu/cpu{0,1,8,16,30,31,32,128}/cache/index3/ 8 0-7,128-135 9 0-7,128-135 10 8-15,136-143 11 16-23,144-151 12 24-31,152-159 13 24-31,152-159 14 32-39,160-167 15 0-7,128-135L1D、L1I 各为 2MiB，单物理核为 32KB，空跑 nop 的 IPC 为 6（有点吓人）。
1 perf stat ./cpu/test 2 Performance counter stats for process id '449650': 3 2,574.29 msec task-clock # 1.000 CPUs uti 4 0 context-switches # 0.000 K/sec 5 0 cpu-migrations # 0.000 K/sec 6 0 page-faults # 0.000 K/sec 7 8,985,622,182 cycles # 3.491 GHz 8 4,390,929 stalled-cycles-frontend # 0.05% frontend 9 4,387,560,442 stalled-cycles-backend # 48.83% backend 10 53,711,907,863 instructions # 5.98 insn per 11 # 0.08 stalled 12 418,902,363 branches # 162.725 M/sec 13 15,036 branch-misses # 0.00% of all b 14 2.574347594 seconds time elapsed 15
