解释 pprof 堆图

Interpreting pprof heap diagrams

当我使用 pprof 分析堆时,我得到以下信息:

但是,我不清楚如何解释该可视化。特别是:

"The memory next to the arrows means _____ and the memory inside of a box means ______. So when a box has multiple arrows from it, it means _____, and when it has multiple arrows to it, it means _____"。

  1. 此函数的感知累积内存消耗包括其所有子函数
  2. 此函数的感知内存消耗不包括它的所有子函数
  3. 它调用多个子函数
  4. 多个函数调用它

堆和 CPU 分析模式之间箭头的含义没有区别。

您可能对 top pprof 命令的输出感兴趣,它可以为您提供以下形式的结果:

9701.61kB of 9701.61kB total (  100%) Dropped 112 nodes (cum <=
48.51kB) Showing top 10 nodes out of 29 (cum >= 3611.54kB)
      flat  flat%   sum%        cum   cum%
 4549.72kB 46.90% 46.90%  4549.72kB 46.90%  mystery.function
 2587.52kB 26.67% 73.57%  2587.52kB 26.67%  reflect.unsafe_NewArray
 1024.02kB 10.56% 84.12%  1024.02kB 10.56%  encoding/xml.copyValue
     514kB  5.30% 89.42%      514kB  5.30%  compress/gzip.NewReader
     514kB  5.30% 94.72%      514kB  5.30%  net/http.(*Transport).dialConn
  512.34kB  5.28%   100%   512.34kB  5.28%  runtime.makeslice
         0     0%   100%      514kB  5.30%  bytes.(*Buffer).ReadFrom
         0     0%   100%  3611.54kB 37.23%  encoding/xml.(*Decoder).Decode
         0     0%   100%  3611.54kB 37.23%  encoding/xml.(*Decoder).DecodeElement
         0     0%   100%  3611.54kB 37.23%  encoding/xml.(*Decoder).unmarshal

这里是(恕我直言)使用 pprof 进行 Go 堆分析的两个最佳参考:

  1. https://google-perftools.googlecode.com/svn/trunk/doc/heapprofile.html
  2. https://software.intel.com/en-us/blogs/2014/05/10/debugging-performance-issues-in-go-programs