HeapAlloc和pprof堆inuse_space数量的巨大差异

Question

我有一个Golang程序，它只实现一个简单的业务逻辑:与服务器端程序建立套接字连接，并维护业务心跳。但是，当此连接不传输任务数据时，pprof报告显示HeapAlloc约为14 it，而inuse_space显示它仅为512 it。为何会有这么大的差异？

pprof HeapAlloc：

# runtime.MemStats
# Alloc = 1386704
# TotalAlloc = 49178232
# Sys = 15285372
# Lookups = 0
# Mallocs = 497504
# Frees = 494691
# HeapAlloc = 1386704
# HeapSys = 12124160
# HeapIdle = 9830400
# HeapInuse = 2293760
# HeapReleased = 8552448
# HeapObjects = 2813
# Stack = 458752 / 458752
# MSpan = 25680 / 32768
# MCache = 1736 / 16384
# BuckHashSys = 727065
# GCSys = 1149056
# OtherSys = 777187
# NextGC = 4194304
# LastGC = 1645580268115312488

go工具pprof mem.prof：

Type: inuse_space
Time: Feb 23, 2022 at 10:23am (CST)
Entering interactive mode (type "help" for commands, "o" for options)
(pprof) top5
Showing nodes accounting for 513.12kB, 100% of 513.12kB total
      flat  flat%   sum%        cum   cum%
  513.12kB   100%   100%   513.12kB   100%  compress/flate.(*huffmanEncoder).generate
         0     0%   100%   513.12kB   100%  compress/flate.init.0
         0     0%   100%   513.12kB   100%  runtime.doInit
         0     0%   100%   513.12kB   100%  runtime.main

Answer 1

，为什么会有这么大的差异？

这是两个不同的度量标准。有关值的定义，请参见https://pkg.go.dev/runtime。它还解释了如何解释这种差异。