Is iTerm2 noticeably slow? I just use the built in Terminal app and I can’t imagine “speed” being a reason to switch away from it. (There is no lack of speed.)

Same, I use it all the time and never perceived it as slow. I am not a tmux user, maybe the speed is noticeable when using more complex terminal apps like that?

The reason I switched from iTerm2 is it took multiple seconds to resize a window on macOS. I use Rectangle to resize windows, and by default my shortcut for "put this window on the left half" cycles through window sizes when the window is already on the left. So a common workflow is to tap Hyper-J to move a window to the left half, then make it the left third, then the left two thirds of the screen. This is fine for any text editor or browser, but iTerm2 would beachball while I waited multiple seconds for it to resize the window.

Wezterm moves instantly.

I’ve noticed that too when the scroll back buffer is particularly long. iTerm seems to then reflow from the beginning, which can take a while.

I keep using a lot of fresh tabs all the time and iTerm resizes instantly via Rectangle for me.

Ghostty was a bit more sluggish in resizing on an Intel Mac than iTerm in the current latest versions.

No, iTerm is not slow. Ghostty is not noticeably faster in any of my workflows. I am sure Ghostty is faster in some use case, but it's nothing I regularly do or have noticed.

Do you have a lot of triggers set up in iTerm 2? IMO that’s what kills performance.

I can understand being frustrated about latency on older Macs — I used to run Alacritty for certain tasks on my Intel Macs for that reason. But on newer Macs like a new M4 Pro I’m back to 100% iTerm 2 again. I can’t fathom having latency problems with iTerm 2 on a new Mac you just unboxed.

Mitchell has a 5 min lightning talk discussing performance of ghostty which is worth a quick watch https://www.youtube.com/watch?v=cPaGkEesw20&t=3015s

It's one of those things that you don't realize how poor the performance is until you experience something better.

Mentioned from his blog: https://mitchellh.com/writing/ghostty-is-coming

> It's one of those things that you don't realize how poor the performance is until you experience something better.

No, it’s one of those things I’ve tested myself extensively and arrived at my own conclusion. Which I already mentioned in the comment you responded to.

The performance talk is about ghostty, which you did not mention trying. You mention alacritty, which is GPU based and offers good performance, but you're quick to rebuttal on unrelated projects.

I only settled on Alacritty after giving all the new and supposedly fast terminal emulators a spin (at least a day for various tasks).