Lint is very slow to start

[Wilfred]

$ touch /tmp/empty.jl
$ time julia -e 'using Lint; lintfile("/tmp/empty.jl")'
julia -e 'using Lint; lintfile("/tmp/empty.jl")'  12.46s user 0.10s system 99% cpu 12.588 total

Is this expected? This is Julia 0.3.1, but I'm seeing worse performance on trunk (~35 seconds). It makes it hard to run the check interactively from Emacs.

[tonyhffong]

Is it possible for you to keep a session of julia open and reuse that session to run lint instead of starting a new julia session every time you lint? Lint, like most packages are compiled just in time, so every function is slow the first time it's run but fast afterwards.

There are also efforts in progress on static compilation of Julia codes:
JuliaLang/julia#8656
JuliaLang/julia#8745

I myself am eagerly watching.

[Wilfred]

It's not possible currently with the standard Emacs lint packages (flycheck, flymake). There's discussion of adding the feature to flycheck, but it's a fairly major API change.

Sounds like this problem will just disappear with the next Julia version. I'll finish the flycheck integration and just live with the slow performance until 0.4 is out.

(I'm open to other suggestions, but I don't see any obvious alternatives.)

[tonyhffong]

Another idea we can steal from emacs itself: client-server model. We could have a session of julia opened with a lint server listening to a port. Any process wanting to lint a piece of code or a file sends that request to the server and gets its output. It'd be faster. Of course none of the code enabling this idea exists.