Add PrecompileTools, precompile runserver

[mkitti]

Add PrecompileTools to and precompile runserver.

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[mkitti]

I'm not sure why Project.toml got rearranged, but it should only be adding PrecompileTools.jl

[mkitti]

julia> using PkgCacheInspector, Pkg

julia> Pkg.develop("LanguageServer")

julia> info_cachefile("LanguageServer")
Contents of /home/mkitti/.julia/compiled/v1.9/LanguageServer/ite7n_4MdHE.so:
  modules: Any[LanguageServer.URIs2, LanguageServer]
  815 external methods
  3756 new specializations of external methods (Base 72.7%, StaticLint 10.1%, JSONRPC 5.0%, ...)
  666 external methods with new roots
  15443 external targets
  11613 edges
  file size:   17084984 (16.294 MiB)
  Segment sizes (bytes):
  system:      5087440 ( 51.21%)
  isbits:      4201270 ( 42.29%)
  symbols:       59097 (  0.59%)
  tags:          73137 (  0.74%)
  relocations:  454313 (  4.57%)
  gvars:         30664 (  0.31%)
  fptrs:         28448 (  0.29%)

[timholy]

Nice. The small amount of residual compilation described in https://discourse.julialang.org/t/precompiling-languageserver-runserver-with-precompiletools-jl/97926 might be fixable by @nospecializing(pipe) on all the IO objects in LanguageServer. (Presumably it doesn't actually run with a IOBuffer.) If you can @snoopi_deep it under "real" usage you can more directly figure out what wasn't covered by your workload.

[pfitzseb]

Very cool! Did you time the difference in startup time?

And yes, we initialize the LS with Base.TTYs instead of IOBuffers.

[timholy]

If printing doesn't have to be high performance, @nospecializing could be a good solution. Otherwise, there's been a request already to set expand PrecompileTools to add a harness capable of instantiating a fake TTY. If there are enough potential customers, adding that harness becomes more worth the downside of making PrecompileTools bigger.

[timholy]

Very cool! Did you time the difference in startup time?

In https://discourse.julialang.org/t/precompiling-languageserver-runserver-with-precompiletools-jl/97926, he shows that @time runserver() goes from 30s to 10s. using LanguageServer goes from 20ms to 500ms, so it seems like a clear win.

[davidanthoff]

Fantastic! I'd say we can merge right away. I'll add PrecompileTools to the extension later today with our submodule way of loading things.

Also, we can probably improve a lot on this, because just running the server probably only executes a relatively small fraction of the code. But let's do that in follow up PRs.

[fredrikekre]

Can

┌ LanguageServer [2b0e0bc5-e4fd-59b4-8912-456d1b03d8d7]
│  ERROR: Endpoint is not running, the current state is closed.
│  Stacktrace:
│   [1] error(s::String)
│     @ Base ./error.jl:35
│   [2] check_dead_endpoint!
│     @ ~/.julia/packages/JSONRPC/Q0FBr/src/core.jl:280 [inlined]
│   [3] get_next_message(endpoint::JSONRPC.JSONRPCEndpoint{IOBuffer, IOContext{IOStream}})
│     @ JSONRPC ~/.julia/packages/JSONRPC/Q0FBr/src/core.jl:212
│   [4] macro expansion
│     @ ~/.julia/packages/LanguageServer/bnyQN/src/languageserverinstance.jl:288 [inlined]
│   [5] (::LanguageServer.var"#113#116"{LanguageServer.LanguageServerInstance})()
│     @ LanguageServer ./task.jl:514
│  [ Info: Shutting down server instance.
└

be silenced? (I assume it comes from this PR)

[mkitti]

I'm missing the part of the error stack trace that connects it with this pull request. Does this happen during precompilation?

[fredrikekre]

Yes

[mkitti]

One option from the code below is to set an error handler. Otherwise, we'll need to modify the else block below.

LanguageServer.jl/src/languageserverinstance.jl

Lines 293 to 299 in 198e07e

	if server.err_handler !== nothing
	server.err_handler(err, bt)
	else
	io = IOBuffer()
	Base.display_error(io, err, bt)
	print(stderr, String(take!(io)))
	end

[mkitti]

Is it just me or does the language server always end with an error?

LanguageServer.jl/src/languageserverinstance.jl

Lines 287 to 290 in 198e07e

	while true
	msg = JSONRPC.get_next_message(server.jr_endpoint)
	put!(server.combined_msg_queue, (type = :clientmsg, msg = msg))
	end