What version of Go are you using (go version)?

$ go version
go version go1.12.7 darwin/amd64
$ gopls version
version v0.1.3-cmd.gopls, built in $GOPATH mode

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (go env)?

$ go env
GOARCH="amd64"
GOBIN=""
GOCACHE="/Users/banks/Library/Caches/go-build"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOOS="darwin"
GOPATH="/Users/banks/src/go"
GOPROXY=""
GORACE=""
GOROOT="/usr/local/Cellar/go/1.12.7/libexec"
GOTMPDIR=""
GOTOOLDIR="/usr/local/Cellar/go/1.12.7/libexec/pkg/tool/darwin_amd64"
GCCGO="gccgo"
CC="clang"
CXX="clang++"
CGO_ENABLED="1"
GOMOD="/Users/banks/src/hashicorp/consul/go.mod"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/8t/n45q26t16fvg2z1hwp1_g2240000gn/T/go-build075442172=/tmp/go-build -gno-record-gcc-switches -fno-common"

What did you do?

1. Checkout https://github.com/hashicorp/consul master, outside of $GOPATH
2. Attempt to use gopls (via VsCode extension)

Relevant VSCode config:

"go.useLanguageServer": true,
      "[go]": {
            "editor.snippetSuggestions": "none",
            "editor.formatOnSave": true,
            "editor.codeActionsOnSave": {
                  "source.organizeImports": true
            },
            "editor.codeActionsOnSaveTimeout": 2000
      },
      "gopls": {
            "usePlaceholders": true // add parameter placeholders when completing a function
      },

I also happen to have GO111MODULE=on in ENV currently as I work with a few repos still in GOPATH but this one is NOT in my GOPATH so I assume this makes no difference as Consul has a go.mod file.

What did you expect to see?

Working Auto-completion, auto-imports, formatting, vet etc.

What did you see instead?

All the above work for a short period (anywhere from 1 minute to 20 mins) or so after restarting the lang server (by reinstalling it or kill -9 the gopls PIDs).

After that the gopls output fills up with lines like this (hundreds of lines, distributed over some/all the files I have open in tabs)

[Error - 13:38:46] unable to check package: context canceled
	file = file:///Users/banks/src/hashicorp/consul/agent/proxycfg/state.go

Shortly after I start seeing those mixed with lots of lines like:

work queue is full

At this point none of the features work until I kill gopls again. Code Helper processes consumes some CPU (but not lots) when in this "hung" state but never seems to resolve even after hours of leaving computer idle. I'm not sure if this is only gopls. After posting I realised that when gopls is working it shows up as gopls in Activity Monitor so I my assumption that Code Helper CPU usage was representing gopls is clearly off. In that case gopls seems to be using virtually no CPU at all in its "hung" state.

This project is pretty large and has a lot of large dependencies (thanks to cloud provider SDKs...) but when it's working gopls is very fast and doesn't seem to use a lot of CPU which makes it seem more "hung" than just working hard on lots of deps.

History and Reproduction

This sounds a lot like the previous issue #31712 but in this case is reproducible for me on an OSS repo.

I've been using VSCode and gopls with current configuration for several months on this repository mostly successfully (several times it has broken and I've had to fiddle with config or something to get it to work but it was previously working). This has been failing in this way reproducibly for me for roughly 3-4 weeks (sorry can't be more precise as I've worked around it assuming it to be temporary for a while). I've tried lots of reconfiguring, upgrading etc. to no avail.

For other smaller libraries, my current configuration doesn't seem to have the same issue. So I assume it's related to the size of the project or some specific issue in one of the deps but have been unable to track down what that might be so far.

I hope this issue is useful as a reproducible case of something others have apparently seen intermittently too but couldn't give a good repro for.