如何在纳秒内制作gprof报告？

Question

我正在尝试使用gprof分析我的C ++应用程序，我想计算函数执行时间。但是，如果某些函数的运行速度超过0.01s，则会在gprof上报告值为0.00。如何将gprof的报告时间更改为纳秒？

感谢您的建议。

    Flat profile:

    Each sample counts as 0.01 seconds.
     no time accumulated

      %   cumulative   self              self     total           
     time   seconds   seconds    calls  Ts/call  Ts/call  name    
      0.00      0.00     0.00        3     0.00     0.00  access_counter
      0.00      0.00     0.00        2     0.00     0.00  get_counter
      0.00      0.00     0.00        1     0.00     0.00  start_counter

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.....

             Call graph (explanation follows)


granularity: each sample hit covers 2 byte(s) no time propagated

index % time    self  children    called     name
                0.00    0.00       1/3           start_counter [3]
                0.00    0.00       2/3           get_counter [2]
[1]      0.0    0.00    0.00       3         access_counter [1]
-----------------------------------------------
                0.00    0.00       2/2           main [9]
[2]      0.0    0.00    0.00       2         get_counter [2]
                0.00    0.00       2/3           access_counter [1]
-----------------------------------------------
                0.00    0.00       1/1           main [9]
[3]      0.0    0.00    0.00       1         start_counter [3]
                0.00    0.00       1/3           access_counter [1]
-----------------------------------------------