Nix-* commands take 17+ minutes to run...is there a way to increase speed? about nix HOT 6 OPEN

using: nix-shell -vvv -j 10 --cores 10 -p nix-info --run "nix-info -m" certainly speeds it up, is there a better way to do this?

You can set both the jobs and cores as options to avoid having to input them every single time. Here's the documentation https://nixos.org/manual/nix/stable/command-ref/conf-file.html?highlight=--max-jobs#conf-max-jobs

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well I suppose the process does eventually finish, but this takes a total of 17 minutes to run... I've updated the issue

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using: nix-shell -vvv -j 10 --cores 10 -p nix-info --run "nix-info -m" certainly speeds it up, is there a better way to do this?

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╰─$ time nix-shell -p nix-info --run "nix-info -m" 1 ↵

• system: "aarch64-darwin"
• host os: Darwin 23.4.0, macOS 14.4.1
• multi-user?: yes
• sandbox: no
• version: nix-env (Nix) 2.21.1
• channels(root): "nixpkgs"
• nixpkgs: /nix/store/qjgi80svyhfcwbnlvzzaqg0nyr7h2w59-source

nix-shell -p nix-info --run "nix-info -m" 3.23s user 1.08s system 10% cpu 39.250 total

╰─$ time nix-shell -j 10 --cores 10 -p nix-info --run "nix-info -m"

• system: "aarch64-darwin"
• host os: Darwin 23.4.0, macOS 14.4.1
• multi-user?: yes
• sandbox: no
• version: nix-env (Nix) 2.21.1
• channels(root): "nixpkgs"
• nixpkgs: /nix/store/qjgi80svyhfcwbnlvzzaqg0nyr7h2w59-source

nix-shell -j 10 --cores 10 -p nix-info --run "nix-info -m" 3.96s user 1.45s system 10% cpu 53.751 total

this adds no speed up... is there a way I can use a cached version of nixpkgs or a cached version of the shell to speed up run time?

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thanks, I'm not going to close this, as its still an issue I'm having on my corporate mac m1, BUT
I'm working around the issue right now by running a nixos vm with no issues.

I do need to use the shell on the host to setup a python environment for my vim settings, so at some point I'll probably just need to setup nix-darwin so the proxy settings and everything run right.
Is there someway I can cache the nixpkgs import in my shell so I can just use a locally pulled copy of nixpkgs?

{ pkgs ? import <nixpkgs> {} }:
pkgs.mkShell {
  packages = [
    (pkgs.python312.withPackages (python-pkgs: [
      # select Python packages here
      python-pkgs.tasklib
      python-pkgs.six
      python-pkgs.packaging
    ]))
    pkgs.python312Packages.pip
  ];
}

that way i only have to deal with this 17 minute download once. Thanks in advance, and I'll post on here if I can figure it out as well

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You could look into [direnv](https://github.com/direnv/direnvl)and [nix-direnv](https://github.com/nix-community/nix-direnv?tab=readme-ov-file#nix-direnv) that combo would cache your devShell. There's at least a NixOS option for comfortably enabling those tho I don't know about nix-darwin.

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