EditorNavigationContribution.onStart is slow

[akosyakov]

It takes over 1s each time.

[kittaakos]

As we have exceeded the 8 seconds, I looked into it. It seems it is not the editor navigator contributions which is slow but waiting for the workspace root to be set for the workspace storage service. For instance, if I remove the await from here:

https://github.com/theia-ide/theia/blob/e147cf39c7f484374b7ec0cd0d04958c3ef00bca/packages/editor/src/browser/editor-navigation-contribution.ts#L79

Then I can see the bundle.js:95521 root WARN DebugFrontendApplicationContribution.onStart is slow, took: 8154.099999985192 ms warning with the same ~8 seconds.

[akosyakov]

Can we restore navigation history async without blocking onStart?

[kittaakos]

Yes, we can but it won't change much. The overall app startup time will remain the same. If not the EditorNavigationContribution blocks, then something else waiting for the WS root will.

According to my measurements (console logging), the bottleneck is here:
https://github.com/theia-ide/theia/blob/e147cf39c7f484374b7ec0cd0d04958c3ef00bca/packages/workspace/src/browser/workspace-service.ts#L142