v7.rc.0 serving 2x - 3x slower than stable versions on my projects

[elvisbegovic]

Bug or Feature ?

- [x] bug report

Command ?

- [x ] serve --sourceMap=false

Versions ?

Angular CLI: 7.0.0-rc.1
Node: 10.9.0
OS: win32 x64
Angular: 7.0.0-rc.0
... common, compiler, compiler-cli, core, forms, http
... language-service, platform-browser, platform-browser-dynamic
... router
Package
@angular-devkit/* 0.9.0-rc.1
@angular-devkit/core 7.0.0-rc.1
@angular-devkit/schematics 7.0.0-rc.1
@angular/cdk 7.0.0-beta.2
@angular/cli 7.0.0-rc.1
@angular/material 7.0.0-beta.2
@ngtools/webpack 7.0.0-rc.1
@schematics/angular 7.0.0-rc.1
@schematics/update 0.9.0-rc.1
rxjs 6.3.3
typescript 3.1.1
webpack 4.19.1

Repro steps ?

Update from 6.2.3 to v7 rc0, it is first time to test cli v7 in my projet.
It is slower even when serving without sourcemaps.
So ng s or ng s --sourceMap=false same refresh cli server around 10seconds while it was around 2-3s before.

Log ?

https://gist.github.com/istiti/9da2393a26aeb0117932e56bb04edd9a

Useful details ?

I can say project is big relativly to what angular/cli can support without bazel (1000+ files) and can't share project unfortunately
I just come back to stable version of cli v.6.2.4 and angular (see working package.json) and I get this score when serving https://gist.github.com/istiti/fc8b629e0a7f7cab13b41b070cbfb94b

Thanks @clydin

[filipesilva]

Heya @istiti thanks for trying you the 7.0 RC!

I'm going to try and repro this regression and see if I can get similar numbers to yours, then see what's causing it.

[Enngage]

I'm experiencing similar/same behavior. In my case the compiler gets stuck on my sass files for a really long time. Prior to this 7.rc.0 version it went through my sass in few seconds, now it takes up to 2-3 minutes. Eventually, it does work fine though.

[filipesilva]

@Enngage do you have a reproduction I can look at?