Extraordinarily gradual Terminal startup on macOS Sequoia (M3 Mac Professional)

Drawback

On my new M3 Mac Professional (36 GB RAM) operating macOS Sequoia 15.3.2, launching a brand new interactive shell in each the constructed‑in Terminal.app and the GPU‑accelerated Ghostty takes orders of magnitude longer than on my Linux/Home windows containers. I incessantly use tmux, and spawning new panes can take > 1 second, whereas on Linux/Home windows it’s < 0.03 s.

What I’ve Tried

1. Stripped-down ~/.zshrc

   • Disabled ALL plugins; nonetheless see preliminary startup ~1.2 s and subsequent ~0.1–0.2 s.

2. Customized timing operate:

timezsh () {
  shell=${1-$SHELL}
  for i in $(seq 1 10); do
    /usr/bin/time $shell -i -c exit
  performed
}

Outcomes (no plugins):

actual 1.24; consumer 0.10; sys 0.05
actual 0.15; consumer 0.04; sys 0.03
actual 0.13; consumer 0.03; sys 0.03
actual 0.14; consumer 0.03; sys 0.03

With plugins enabled:

3. compinit tweaks & zprof evaluation

   • Precompiled cache, eliminated previous dump information, no important enchancment.

4. Homebrew & some cli instruments additionally really feel sluggish, suggesting a deeper system concern.

Surroundings

• macOS: Sequoia 15.3.2
• {Hardware}: Apple M3 Professional, 36 GB RAM
• Shells examined:
  • /bin/zsh (default)
  • /bin/bash
• Measurement software: /usr/bin/time and zprof

Questions

Has anybody noticed 1-2 second chilly startup on an M3 Mac for Zsh, even with minimal config?
Are there recognized system-wide elements (e.g. Rosetta layers, filesystem checks, notarization delays) that would decelerate each new shell occasion?
How can I diagnose what’s taking place throughout that 1 second (e.g. tracing dynamic libraries, file-system stalls)?
Any tweaks or workarounds to get terminal/spawn occasions nearer to < 0.1 s?

Thanks upfront for any insights!