(Still) Slow package detection on Nix

[soupdiver]

When running fastfetch --stat I have 2 sections that take quite some time and its annoying when starting a new shell.

Packages 328 (nix-system), 56 (nix-default), 12 (brew-cask)   232.282ms

Display (Dell AW3821DW) 3840x1600 @ 144 Hz in 38" [External]        36.930ms

I saw that there were alreadys PRs in the past to speed up nix package detection but it's still so slow. Also not sure why display detection takes so long. Is there any way to cache those values maybe?

[CarterLi]

Are you on Linux or macOS?

[soupdiver]

Are you on Linux or macOS?

macOS 15.6

[CarterLi]

All the past PRs were for Linux. It doesn't seem anyone cares Nix on macOS, so...

[soupdiver]

All the past PRs were for Linux. It doesn't seem anyone cares Nix on macOS, so...

I see 🥲

[CarterLi]

I can port the changes introduced in the PRs to macOS, if you want to test it.

[soupdiver]

I can port the changes introduced in the PRs to macOS, if you want to test it.

Sure, Im up for it.
I was just looking at the code... It's this bit here I guess:

fastfetch/src/detection/packages/packages_apple.c

Lines 49 to 71 in 3ef8483

	static uint32_t getNixPackagesImpl(const char* path)
	{
	//Nix detection is kinda slow, so we only do it if the dir exists
	if(!ffPathExists(path, FF_PATHTYPE_DIRECTORY))
	return 0;
	FF_STRBUF_AUTO_DESTROY output = ffStrbufCreateA(128);
	//https://github.com/fastfetch-cli/fastfetch/issues/195#issuecomment-1191748222
	FF_STRBUF_AUTO_DESTROY command = ffStrbufCreateA(255);
	ffStrbufAppendS(&command, "for x in $(nix-store --query --requisites ");
	ffStrbufAppendS(&command, path);
	ffStrbufAppendS(&command, "); do if [ -d $x ]; then echo $x ; fi ; done | cut -d- -f2- | egrep '([0-9]{1,}\\.)+[0-9]{1,}' | egrep -v '\\-doc$|\\-man$|\\-info$|\\-dev$|\\-bin$|^nixos-system-nixos-' | uniq | wc -l");
	ffProcessAppendStdOut(&output, (char* const[]) {
	FASTFETCH_TARGET_DIR_ROOT "/bin/sh",
	"-c",
	command.chars,
	NULL
	});
	return (uint32_t) strtoul(output.chars, NULL, 10);
	}

?

[CarterLi]

@soupdiver 4004501

Please test

[soupdiver]

@soupdiver 4004501

Please test

From

Packages 333 (nix-system), 56 (nix-default), 12 (brew-cask)                  357.292ms

To

Packages 333 (nix-system), 56 (nix-default), 12 (brew-cask)               155.775ms

Still have this annoying delay when opening my Terminal since I run fastfetch on shell start.
Maybe I have to tinker with some local caching... but thanks a lot for the effort. Already took a good chunk out of the processsing time 🫶

[CarterLi]

Even when cached?

[CarterLi]

Anyway, you can always disable it in JSON config with modules.packages.disabled

[soupdiver]

Anyway, you can always disable it in JSON config with modules.packages.disabled

yup, saw that 👍

Even when cached?

Uhm, when is the cache hit? When I execute fastfetch the second time or?