[Bug]: watcher blocks CPU after each rebuild

[vkurchatkin-miro]

System Info

ystem: OS: macOS 14.5 CPU: (10) arm64 Apple M1 Pro Memory: 167.59 MB / 32.00 GB Shell: 5.9 - /bin/zsh Binaries: Node: 20.11.0 - ~/.volta/tools/image/node/20.11.0/bin/node Yarn: 4.1.0 - ~/.volta/tools/image/yarn/1.22.10/bin/yarn npm: 10.2.4 - ~/.volta/tools/image/node/20.11.0/bin/npm Browsers: Chrome: 127.0.6533.99 Safari: 17.5 npmPackages: @rspack/cli: 1.0.0-beta.1 => 1.0.0-beta.1 @rspack/core: 1.0.0-beta.1 => 1.0.0-beta.1 @rspack/plugin-react-refresh: 1.0.0-beta.1 => 1.0.0-beta.1

Details

In our setup after each interactive rebuild the watcher is restarted and blocks the CPU for ~2 seconds. Subsequently HMR or live reloading is delayed for this amount of time.

It looks like watching is restarted from scratch after every rebuild here: https://github.com/web-infra-dev/rspack/blob/2bd905d47e731772365637188c929f5371e60267/packages/rspack/src/node/NodeWatchFileSystem.ts#L66

while it is not necessary and the watcher instance can be reused (watchpack supports watch to be called again so that it can only create watchers that don't exists).

Reproduce link

No response

Reproduce Steps

N/A