[flurrything]

> For users, I hope Remacs will be faster

The main reason my emacs is painfully slow is that most elisp code blocks. Stuff like hitting tab for auto-completion might perform a blocking query from a language server hanging emacs for multiple seconds. Opening a file tries to start a language server and blocks the editor in the process. Etc.

Making emacs itself faster won't make the experience of working with emacs any better.

[pulisse]

> The main reason my emacs is painfully slow is that most elisp code blocks.

Note that multithreading is now in Emacs master, and some core packages (e.g., Tramp, which used to block when opening a remote file) have already been updated to make use of it, so starting with the next major release things will be improving on this front.

[simias]

Some things like indenting a large file or even searching in a huge buffer can be quite slow. For instance I just tried indenting a ~1000line C buffer and it took about 2 seconds. When dealing with very large files (hundreds of MB) some basic movement and editing commands can be quite slow. Dealing with very large TAGS file (for the linux kernel for instance) is annoyingly laggy as well.

I agree that it's not the panacea though, Emacs would benefit from using a more threaded or event-oriented programming model for many things.

[ams6110]

Emacs does block on many operations, but I've never had it be really noticeable on tab-completion type stuff.

Though I only use auto-complete on emacs commands, so maybe I've just missed it.

[db48x]

It depends quite a lot on what kind of autocompletion you're using, for which language. It's a mixed bag.