The Zed Debugger Is Here

It's surprisingly slow. Switching files in the tab list has a noticeable delay. Typing is higher latency than both Emacs (lsp-mode activated) and my web browser. Also uses approximately 60MiB more than my Emacs. It starts fast though!

I wouldn't complain about this stuff if it wasn't for their tagline being 'it's fast' and they're losing to Emacs Lisp (not a language amenable to being very fast) with a highly optimized C core.

I looked at their plugins, they're compiled into WASM and run in some VM. Maybe that's part of it?

> I looked at their plugins, they're compiled into WASM and run in some VM. Maybe that's part of it?

No. The ones I've looked just set up stuff, like launching a language server. They shouldn't be involved in typing.

I think it's related to the GPU usage. It's easy to introduce delays when you do GPU compositing, and the OS will already be doing its own.

As for emacs, IIRC they did some ugly things to update the UI directly instead of going through the normal event loop, which was causing compatibility issues later on.

Talking of Emacs, there is a very well designed DAP-based debugger available as the 'dape' package.

https://elpa.gnu.org/packages/dape.html

The way it's designed (incl. having no dependencies) suggests that they will be angling for it to be included with stock Emacs at some point.

How did you manage to make zed slower than emacs? From my experience, latency in zed sometimes even feels negative. Everything is instant: editing, lsp commands, file switching

In contrast, all my attempts at emacs ended up in dropping it due to latency issues (mostly because I work on remote machines)

It's probably something in the rendering pipeline. What operating system?

I think you answered how you managed to induce latency in Emacs :).

Fedora 41, KDE Plasma 6.3.5, kernel 6.14.5, Wayland, Mesa Intel Iris Xe Graphics.