Here's a fake completion provider that returns 20k items. Its resolve method does nothing (but exists, so that VS Code thinks it may be used - that seems to be important).
export class FakeCompletionItemProvider implements CompletionItemProvider {
public async provideCompletionItems(
document: TextDocument, position: Position, token: CancellationToken, context: CompletionContext,
): Promise<CompletionList> {
const items: CompletionItem[] = Array<CompletionItem>(20000);
for (let i = 0; i < items.length; i++) {
const item = new CompletionItem(`Item ${i}`);
item.filterText = `${item.label}???`;
item.kind = CompletionItemKind.Constant;
item.detail = "(deprecated)";
item.documentation = "docs";
item.insertText = `${item.label} !!`;
item.keepWhitespace = true;
item.commitCharacters = ["["];
item.command = {
command: "editor.action.triggerSuggest",
title: "Suggest",
};
items[i] = item;
}
return new CompletionList(items);
}
public async resolveCompletionItem(item: DelayedCompletionItem, token: CancellationToken): Promise<CompletionItem | undefined> {
return undefined;
}
}If you register this provider, then repeatedly invoke completion (I found the easiest way to do this was inserting lots of newlines then hitting Ctrl+Space then Backspace repeatedly), the memory grows continiously and is never reclaimed.
I believe this may be what my users are seeing in Dart-Code/Dart-Code#1721 and flutter/flutter#33280 and I saw in #74390. After many the extension host crashes being out of memory.
@jrieken FYI (relates a little to what I was trying to repro with #74418, but did badly because I removed resolve).
Here's a fake completion provider that returns 20k items. Its resolve method does nothing (but exists, so that VS Code thinks it may be used - that seems to be important).
If you register this provider, then repeatedly invoke completion (I found the easiest way to do this was inserting lots of newlines then hitting
Ctrl+SpacethenBackspacerepeatedly), the memory grows continiously and is never reclaimed.I believe this may be what my users are seeing in Dart-Code/Dart-Code#1721 and flutter/flutter#33280 and I saw in #74390. After many the extension host crashes being out of memory.
@jrieken FYI (relates a little to what I was trying to repro with #74418, but did badly because I removed resolve).