Typing is laggy when outline is visible

[joaomoreno]

Steps:

1. Open vscode-docs
2. Open release-notes/v1_45.md
3. Make sure outline is visible in the sidebar
4. Type some text

Here's the profile screenshot with outline open:

With outline closed:

cc @jrieken

[joaomoreno]

Figured out that this is called on every keystroke:

vscode/src/vs/workbench/contrib/outline/browser/outlinePane.ts

Line 613 in 68213a7

this._tree.updateChildren();

This is odd, especial because getLiveMarkers(textModel) always returns an empty collection:

vscode/src/vs/workbench/contrib/outline/browser/outlinePane.ts

Line 606 in 68213a7

for (const [range, marker] of this._markerDecorationService.getLiveMarkers(textModel)) {

So why is onDidChangeMarker actually firing?

vscode/src/vs/workbench/contrib/outline/browser/outlinePane.ts

Line 617 in 68213a7

this._editorDisposables.add(this._markerDecorationService.onDidChangeMarker(updateMarker));

[jrieken]

Adding @sandy081 who wrote that marker service and because this likely affects the markers panel?

[jrieken]

This doesn't reproduce for me, e.g no slow typing or freezing nor does the FPS change when toggling outline.problems.enabled. The CPU profiles shows that very little time is spend in updateMarker (when typing four times console.log();\n in TS files that already has some errors).

I am not arguing that it is smart to always call this function but I definitetly see no slowing, freezing and anything remotely related to that.

[jrieken]

Freeze only repos on windows (linux unknown, mac not)

[jrieken]

The event firing soo often is actually the right thing because it means (bad naming) ranges of diagnostics markers of this file have changed. And that happens when typing... I will debounce this in the outline view

[jrieken]

Pushed change to debounce the onDidChangeMarker inside the outline pane (see comment above) and I also don't send the event when before and after no marker where there

@sandy081 leaving the rest to you. Idk how else this service is used and if its internal content change listener should be debounced or not. I feel it should but idk how that affects other consumers. This call/event:

vscode/src/vs/editor/common/services/markerDecorationsServiceImpl.ts

Line 118 in d2c6b2c

markerDecorations.register(model.onDidChangeContent(() => this._updateDecorations(markerDecorations)));

[joaomoreno]

Thanks @jrieken, debouncing is definitely a good change.

But yeah, there's still the question of why is that even firing at all, when there aren't any changes to the markers.

[sandy081]

I introduced IMarkerDecorationsServiceinitially for Monaco editor to show squiggles and hovers.

@jrieken Seems you added onDidChangeMarker and getLiveMarkers afterwards and OutlinePane is the only consumer.

Please change it according to the needs of OutlinePane.

[jrieken]

@sandy081 please read carefully. This is the underlying problem that's remaining: 404f66c

[sandy081]

Sorry @jrieken. I just focused on last comment - #96914 (comment)

Also debounced the internal content change event.