如何调试FlowType运行性能极度缓慢的问题

工作中需要使用FlowType，但它运行速度极其缓慢，已尝试删除flow-typed定义、消除循环依赖等多种优化方案，问题仍未解决。目前没有更多排查思路，也不清楚该如何调试该问题，想要了解有没有方法可以查看每次保存/敲击键盘后生成的依赖树。

编辑1 #

以下是当前使用的.flowconfig配置：

[ignore]
.*/node_modules/react-native-keyboard-aware-scroll-view/.*
.*/node_modules/react-native-fbsdk/.*
.*/node_modules/@react-native-community/picker.*
.*/node_modules/@react-native-community/slider.*
; remove when flow is updated. Currently leads to "Cannot assign rest to restState because rest [1] is incompatible with State [2]."
.*/node_modules/redux-persist/lib/persistReducer.js.flow
.*/node_modules/recompose/dist/Recompose.cjs.js.flow

; Ignores sub apps
.*/firebase/**
.*/webapp/**
.*/node_modules/react-native-androw/src.*

; Migration to RN 0,64 causes some random errors
.*/node_modules/react-navigation-redux-helpers
.*/node_modules/react-navigation-redux-helpers
.*/node_modules/react-native-calendars
; .*/node_modules/react-native/Libraries/Interaction
; .*/node_modules/react-native/Libraries/Logbox/Data

; We fork some components by platform
.*/*[.]android.js

; Ignore "BUCK" generated dirs
<PROJECT_ROOT>/\.buckd/

; Ignore polyfills
node_modules/react-native/Libraries/polyfills/.*

; Flow doesn't support platforms
.*/Libraries/Utilities/LoadingView.js

[untyped]
.*/node_modules/@react-native-community/cli/.*/.*
.*/node_modules/react-native-confetti-cannon/.*
.*/node_modules/react-native-linear-gradient/.*


[libs]
node_modules/react-native/interface.js
node_modules/react-native/flow/
flow/libs

[options]
emoji=true
server.max_workers=1
sharedmemory.hash_table_pow=22

esproposal.optional_chaining=enable
esproposal.nullish_coalescing=enable
; RN 0.64 turns this on, our codebase explodes
; exact_by_default=true
module.file_ext=.js
module.file_ext=.json
module.file_ext=.ios.js
module.system.node.allow_root_relative=true
munge_underscores=true
module.name_mapper='^react-native/\(.*\)$' -> '<PROJECT_ROOT>/node_modules/react-native/\1'
module.name_mapper='^@?[./a-zA-Z0-9$_-]+\.\(bmp\|gif\|jpg\|jpeg\|png\|psd\|svg\|webp\|m4v\|mov\|mp4\|mpeg\|mpg\|webm\|aac\|aiff\|caf\|m4a\|mp3\|wav\|html\|pdf\)$' -> '<PROJECT_ROOT>/node_modules/react-native/Libraries/Image/RelativeImageStub'
module.name_mapper.extension='svg' -> '<PROJECT_ROOT>/flow/SVGFlowStub.js'

suppress_type=$FlowIssue
suppress_type=$FlowFixMe
suppress_type=$FlowFixMeProps
suppress_type=$FlowFixMeState

; Types first is the architecture that forces very very strict rules (always export typed results)
; In order to increase the performance of flow (it is painfully slow)
; However our codebase is in no way shape or form ready for this (it throws around 567 type errors)
types_first=false

[lints]
sketchy-null-number=warn
sketchy-null-mixed=warn
sketchy-number=warn
untyped-type-import=warn
nonstrict-import=warn
deprecated-type=warn
unsafe-getters-setters=warn
unnecessary-invariant=warn
signature-verification-failure=warn

[strict]
deprecated-type
nonstrict-import
sketchy-null
unclear-type
unsafe-getters-setters
untyped-import
untyped-type-import

[version]
^0.137.0

还尝试更换了其他Flow插件，原本怀疑问题和插件向Flow服务器发送过多请求有关，更换后性能仅有小幅提升，没有明显改善。

编辑2 #

又尝试了多种方案，包括删除为recompose编写的大量类型定义，将大量类型提取到libDef中，依然没有效果。判断问题出在项目架构上：所有类型都声明在types/index.js文件中，每次使用都需要手动导入，比如import type { UUID } from 'src/types'，正因为所有类型都集中声明在这里，所以每次修改保存后Flow都需要检查400+文件，依赖树本身没有问题。

编辑3 #

最终解析了整个应用的依赖树来排查问题，得出的结论是Flow本身没有问题，问题出在导入逻辑上，主要是Redux和Sagas的导入逻辑导致只要导入一个内容就会触发整个应用的重新检查。

内容的提问来源于stack exchange，提问作者Oscar Franco