cache_calibrator

cache_calibrator 可以测量 cache 相关的性能参数。

安装 cache_calibrator：

apt install -y cache-calibrator

ICE-EVB 开发板测试：

cache_calibrator 1200 10M file

在 ICE-EVB 开发板上运行结果如下：

Calibrator v0.9e
(by Stefan.Manegold@cwi.nl, http://www.cwi.nl/~manegold/)
e16a9010 274364796944 4096    16
e16a9fff 274364801023 4096  4095
e16aa000 274364801024 4096     0

MINTIME = 10000

analyzing cache throughput...
      range      stride       spots     brutto-  netto-time
   10485760           8     1310720       17472         273

analyzing cache latency...
      range      stride       spots     brutto-  netto-time
   10485760           8     1310720      139776         273

analyzing TLB latency...
      range      stride       spots     brutto-  netto-time
    1474560        1152        1280       18176        1136


CPU loop + L1 access:       2.50 ns =   3 cy
             ( delay:       0.00 ns =   0 cy )

caches:
level  size    linesize   miss-latency        replace-time
  1     64 KB  128 bytes    9.19 ns =  11 cy    9.16 ns =  11 cy
  2      2 MB  128 bytes   19.05 ns =  23 cy   19.09 ns =  23 cy

TLBs:
level #entries  pagesize  miss-latency
  1       20       4 KB     3.34 ns =   4 cy 

# ls
file.cache-replace-time.gp
file.TLB-miss-latency.data
file.TLB-miss-latency.gp
file.cache-miss-latency.data
file.cache-miss-latency.gp
file.cache-replace-time.data

其中 1200表示 1200MHz，也就是 1.2GHz，也即 ICE 开发板的 CPU 频率；跑完后生成了很多以“file”开头的文件，可以观测 cache 各个方面的性能。