vue 项目在 hmr 时 rebuild 特别慢

修改一行就要 rebuild 大概 10s，这效率没法干活了 T_T 看了不少文章说开 dllPlugin 有效，但我们这项目实测也没用

贴个 progress

webpack: Compiling...
308ms building modules
50ms sealing
0ms optimizing
0ms basic module optimization
6ms module optimization
3ms advanced module optimization
53ms basic chunk optimization
0ms chunk optimization
0ms advanced chunk optimization
0ms module and chunk tree optimization
0ms chunk modules optimization
1ms advanced chunk modules optimization
13ms module reviving
0ms module order optimization
5ms module id optimization
6ms chunk reviving
3ms chunk order optimization
10ms chunk id optimization
44ms hashing
5ms module assets processing
76ms chunk assets processing
39ms additional chunk assets processing
0ms recording
418ms additional asset processing
0ms chunk asset optimization
8396ms asset optimization
 95% emitting

 DONE  Compiled successfully in 9512ms

查不到这个 asset optimization 在做啥

 + 52 hidden assets
 [466] (webpack)/hot nonrecursive ^\.\/log$ 170 bytes {5} [built]
       [] -> factory:1ms dependencies:0ms = 1ms
 [499] ./node_modules/moment/locale ^\.\/.*$ 2.88 kB {5} [optional] [built]
       [] -> factory:0ms building:0ms dependencies:1ms = 1ms
[1048] ./src/module/user/userCredit/userCredit.vue 1.57 kB {7} [built]
       [] -> factory:0ms building:1ms dependencies:5318ms = 5319ms
[1050] ./node_modules/css-loader?{"minimize":false,"sourceMap":false}!./node_modules/vue-loader/lib/style-compiler?{"vue":true,"id":"data-v-4eeb260f","scoped":true,"hasInlineConfig":false}!./node_modules/sass-loader/lib/loader.js?{"sourceMap":false}!./node_modules/sass-resources-loader/lib/loader.js?{"resources":"/Users/linxi/Develop/maitao/h5-refactor/src/common/scss/variables.scss"}!./node_modules/vue-loader/lib/selector.js?type=styles&index=0!./src/module/user/userCredit/userCredit.vue 4.01 kB {7} [built]
       [] -> factory:0ms building:0ms dependencies:1ms = 1ms
[1060] ./node_modules/babel-loader/lib!./node_modules/vue-loader/lib/selector.js?type=script&index=0!./src/module/user/userCredit/userCredit.vue 5.69 kB {7} [built]
       [] -> factory:1ms building:44ms dependencies:14ms = 59ms
[1061] ./node_modules/vue-loader/lib/template-compiler?{"id":"data-v-4eeb260f","hasScoped":true,"transformToRequire":{"video":"src","source":"src","img":"src","image":"xlink:href"},"buble":{"transforms":{}}}!./node_modules/vue-loader/lib/selector.js?type=template&index=0!./src/module/user/userCredit/userCredit.vue 3.15 kB {7} [built]
       [] -> factory:1ms building:58ms = 59ms
    + 1156 hidden modules

就是当前修改的那个 vue 文件 dependencies 耗时巨长

项目是拿 vue-cli 建出来的，不知道怎么能进一步 profile?