meta: VS Code Vim becomes very very slow

Many people report this plugin slows down.

For me it becomes unbearably slow after a while (f.e. 1 key stroke per second, and they all get backed up while other VS Code actions can happen mid-way causing jumbled results).

Possibly related:

• https://github.com/VSCodeVim/Vim/issues/9708
• https://github.com/VSCodeVim/Vim/issues/8924
• https://github.com/VSCodeVim/Vim/issues/8557
• https://github.com/VSCodeVim/Vim/issues/8517
• https://github.com/VSCodeVim/Vim/issues/8115
• https://github.com/VSCodeVim/Vim/issues/7898
• https://github.com/VSCodeVim/Vim/issues/7804
• https://github.com/VSCodeVim/Vim/issues/7546
• https://github.com/VSCodeVim/Vim/issues/7415
• https://github.com/VSCodeVim/Vim/issues/7274
• maybe https://github.com/VSCodeVim/Vim/issues/6628
• https://github.com/VSCodeVim/Vim/issues/6589
• https://github.com/VSCodeVim/Vim/issues/5339
• https://github.com/VSCodeVim/Vim/issues/4728
• https://github.com/VSCodeVim/Vim/issues/4598#issuecomment-591769018
• https://github.com/VSCodeVim/Vim/issues/4293
• https://github.com/VSCodeVim/Vim/issues/4283
• https://github.com/VSCodeVim/Vim/issues/3957
• https://github.com/VSCodeVim/Vim/issues/3508
• https://github.com/VSCodeVim/Vim/issues/8887
• https://github.com/VSCodeVim/Vim/issues/8573
• https://github.com/VSCodeVim/Vim/issues/7301
• https://github.com/VSCodeVim/Vim/issues/6830 (still a problem)
• https://github.com/VSCodeVim/Vim/issues/6169
• https://github.com/VSCodeVim/Vim/issues/5188 (still problematic)
• https://github.com/VSCodeVim/Vim/issues/4941 (still problematic)
• https://github.com/VSCodeVim/Vim/issues/4309
• https://github.com/VSCodeVim/Vim/issues/4088
• https://github.com/VSCodeVim/Vim/issues/3924
• https://github.com/VSCodeVim/Vim/issues/3654

(I went to page 2 only, for both open and closed issues, searching "slow")

Related:

• https://github.com/VSCodeVim/Vim/issues/8603

It might be "Microsoft's" fault for the extension API design? From https://github.com/VSCodeVim/Vim/issues/4598#issuecomment-591769018:

FWIW, I just tried amVim and it has the same issue. Perhaps the Extension Host is to blame for this? I would not be surprised, I think the Extension Host is garbage, and causes way more problems than it was intended to solve. (VSCodeVim commands do have to run in the separate extension host process right? It's pretty ridiculous for every key press to be doing IPC roundtrips, which is why I hate the Extension Host architecture for giving you no other option...)

I switched to Simple Vim

and it is a lot smoother.

In insert mode, it's just native VS Code, and the plugin listens only for Escape to go back to Normal mode. It's not as full featured, but enough for me to get productive without slowdowns, and to save my sanity.

Simple Vim still suffers from the same issues (seems like Extension Host), but it's doing a lot less so the issues aren't as pronounced.

The issue does not name files, tests, or an entry point. Start by reproducing the slowdown and comparing the linked reports, especially the Extension Host and keypress behavior described here. Done should mean identifying a specific, actionable cause and a verified performance improvement.