[RFC] Defer vim-state.coffee loading

[maxxk]

I was wondering is it acceptable to defer vim-state.coffee loading until the first text editor is created?

On my machine with this change vim-mode loading time goes from ~100ms down to ~15ms.
On the other hand, this change will slow down first text editor opening a bit.

Change was proposed by @lee-dohm in atom/atom#2654.

[maxbrunsfeld]

In my opinion, since this won't help the common case of starting Atom with text editors open, it isn't worth lazy-loading in this case. I'm open to arguments in favor of doing it though.

[bronson]

Things have gotten a fair bit faster since this PR was filed. I figured I'd run this test again...

Test

• git clone bronson/vim-mode # (to get the rebased lazy loading branch)
• apm link vim-mode

Now, to perform the test, I launched Atom, opened timecop, and recorded vim-mode's startup time. I ran the following commands alternately so each startup was very warm.

• git checkout lazy-loading; sleep 0.5; atom .
• git checkout master; sleep 0.5; atom .

Results

Lazy	Master
19ms	30ms
18ms	30ms
18ms	31ms

Stable and definitive: on my machine, this technique saves 10ms / ~30%.

Conclusion

18ms is worthy of a gold highlight-warning and 30ms is the red highlight-error. This PR might get vim-mode out of the doghouse it shares with status-bar.

That said, I agree with @maxbrunsfeld: every time I open my editor, I'm going straight into a Vim window. For me, all this patch does is reorder the load process. It doesn't actually save any real-world time. Doesn't seem worth it.

[maxbrunsfeld]

Thanks @bronson. I think we'll need to use some different tactics for improving the package's load time. Closing this out.