callback 和 promise 性能差距疑问

callback

import * as fs from 'fs'; import * as path from 'path'; function list_dir(dir: string) { fs.readdir(dir, 'utf-8', (err, files) => { files.forEach(file => { file = path.join(dir, file) fs.stat(file, (err, stat) => { if (stat.isDirectory()) { list_dir(file) } if (stat.isFile()) { file // console.log("%O", file); } }) }); }) } list_dir('.') 

promise

import * as util from 'util'; import * as fs from 'fs'; import * as path from 'path'; async function list_dir(dir: string) { const readdir = util.promisify(fs.readdir); const stat = util.promisify(fs.stat); const files = await readdir(dir, 'utf-8') files.forEach(async file => { file = path.join(dir, file) const state = await stat(file) if (state.isDirectory()) { await list_dir(file) } if (state.isFile()) { file // console.log("%O", file); } }) } list_dir('.') 

性能测试结果

node /workspaces/typescript $ time node promise.js && time node callback.js real 0m1.140s user 0m1.136s sys 0m1.292s real 0m0.377s user 0m0.368s sys 0m0.534s node /workspaces/typescript $ time node promise.js && time node callback.js real 0m1.062s user 0m1.132s sys 0m1.184s real 0m0.538s user 0m0.470s sys 0m0.784s node /workspaces/typescript $ time node promise.js && time node callback.js real 0m1.194s user 0m1.221s sys 0m1.308s real 0m0.436s user 0m0.393s sys 0m0.651s node /workspaces/typescript $ time node promise.js && time node callback.js real 0m1.024s user 0m1.165s sys 0m1.027s real 0m0.416s user 0m0.313s sys 0m0.653s node /workspaces/typescript $ nodejs --version v16.3.0 node /workspaces/typescript $ tsc --version Version 4.3.5 

有性能差异可以理解，但是这个性能差异过大，请问各位是我的写法有问题，还是其它原因导致的呢？