go doc consuming CPU

[aplsek]

I am seeing high CPU consumed by the 'doc' subprocesses. This started happening in the last two weeks after the latest release. The following 4 processes are spawned as soon as I start typing into a .go file, I have a single editor window opened:

Visual Studio Version: 1.25.0-insider
Go plugin: 0.7.0

Is there a way howto disable go doc or howto analyze this further?

[ramya-rao-a]

As far as I know, the Go extension doesn't use any tool called doc. In the recent release, we did start using go doc though, but that should have shown up as go not doc

Can you disable all other extensions and see if you still see the issue?

[aplsek]

The 'doc' in Activity Monitor represents a go doc process. See my ps output, its spawn by Visual Code:

501  5736 94581   0 10:22AM ??         0:00.03 /usr/local/bin/go doc -c -cmd -u github..... Foo
501 94581 94580   0  9:41AM ??         0:05.51 /private/var/folders/07/2nk35j995fx2hjw9zkhhlwn40000gn/T/AppTranslocation/7BC4D181-308D-4B83-956E-1E0374DC5EAE/d/Visual Studio Code - Insiders.app/Contents/Frameworks/Code - Insiders Helper.app/Contents/MacOS/Code - Insiders Helper /private/var/folders/07/2nk35j995fx2hjw9zkhhlwn40000gn/T/AppTranslocation/7BC4D181-308D-4B83-956E-1E0374DC5EAE/d/Visual Studio Code - Insiders.app/Contents/Resources/app/out/bootstrap --type=extensionHost 

[ramya-rao-a]

@aplsek doc is an argument for the go command, so wouldn't the Activity Monitor have the process name as go instead of doc?

Select the process in the Activity Monitor, and then select the "info" button on the top, that will open up a detailed view which will have the parent information. Check if the processes with the process name doc have VS Code as the parent.

Another thing to try is to run Developer: Open Process Explorer in VS Code. This will open the process explorer and any high CPU consuming processes will show up there

[grillbiff]

Hi, I'm experiencing the same problem. Here is the process chain of one of the doc processes. Couldn't see anything strange in the process explorer though

Two processes with a common parent down the line.

[ramya-rao-a]

Thanks for that @grillbiff. These are for doc processes as shown in the screenshot in
#2152 (comment)?

We use go doc for 2 features:

• The information you see when you hover on code text.
• The information you see on the side in the auto-completion widget.

Lets try and disable these 2 features and see if that helps your case.

For the first feature, lets use gogetdoc instead of go doc for the hover info

• Add the setting "go.docsTool": "gogetdoc"
• Run the command Go: Install/Update tools
• Select gogetdoc and press Ok to install it

For the second feature, if you are seeing the documentation on the side like in the below picture, press Ctrl+Space to hide it.

[grillbiff]

Hi,
yes my image is for two of the doc processes shown in #2152 (comment).

I tried changing to both gogetdoc and guru but no luck, still creating a lot of doc processes.

[ramya-rao-a]

@grillbiff Also ensure that the docs side of the completions are not expanded.

[grillbiff]

@ramya-rao-a I think it has been disabled, the documentation does not appear unless I explicitly press the small info icon

[grillbiff]

I still get alot of doc processes. Could it be that VSCode is using godoc regardless of my choice?

[ramya-rao-a]

Ah! My mistake.

So, VS Code always calls resolveCompletionItem for each completion item in focus whether it is expanded for docs or not.

The Go extension which implements this resolveCompletionItem calls go doc to fetch the docs and return it to VS Code which then displays it to you.

I was under the assumption that this resolveCompletionItem is only called when the docs section is expanded.

I have pushed a fix for this. Can you try it out?

• First install the beta-version of this extension
• Update the go.gocodeFlags setting as below

"go.gocodeFlags": [
		"-builtin",
		"-ignore-case",
		"-unimported-packages",
                "-exclude-docs"
	]

The first 3 are flags that will get passed to gocode to give us the completions. The last one will be used by the Go extension to not run go doc to get the docs.

Remember to kill all existing processes for go doc before trying this out.

[grillbiff]

Hi,
installed the fix and use -exclude-docs which seems to work. VSCode no longer creates multiple doc processes. Tested with both godoc and gogetdoc and both works fine so maybe the issue was with the resolveCompletionItem all along?

[ramya-rao-a]

Thats right @grillbiff

[aplsek]

Hi,

Is there an ETA on when the fix is going to be part of the official release?

Not sure I want to install beta-version of the plugin as that would block the future updates...

Thanks!

[ramya-rao-a]

The latest update (0.9.1) to the extension has this fix.