More minimization work

flake.lock

@@ -69,11 +69,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1728492678,
-        "narHash": "sha256-9UTxR8eukdg+XZeHgxW5hQA9fIKHsKCdOIUycTryeVw=",
+        "lastModified": 1728888510,
+        "narHash": "sha256-nsNdSldaAyu6PE3YUA+YQLqUDJh+gRbBooMMekZJwvI=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "5633bcff0c6162b9e4b5f1264264611e950c8ec7",
+        "rev": "a3c0b3b21515f74fd2665903d4ce6bc4dc81c77c",
         "type": "github"
       },
       "original": {

flake.nix

@@ -36,15 +36,18 @@
             {
               nativeBuildInputs = with pkgs; [
                 erofs-utils
-                xz
+                zstd
               ];
             }
             ''
               mkdir -p $out
-              xz -1 -cz ${config.system.build.uki}/${config.system.boot.loader.ukiFile} \
-                > $out/${config.system.boot.loader.ukiFile}.xz
-              xz -1 -cz ${config.system.build.image}/${config.boot.uki.name}_${config.system.image.version}.store.raw \
-                > $out/${config.boot.uki.name}_${config.system.image.version}.img.xz
+              cp ${config.system.build.image}/${config.boot.uki.name}_${config.system.image.version}.store.raw $out/
+
+              zstd -9 ${config.system.build.uki}/${config.system.boot.loader.ukiFile} \
+                -o $out/${config.system.boot.loader.ukiFile}.zst
+
+              zstd -9 ${config.system.build.image}/${config.boot.uki.name}_${config.system.image.version}.store.raw \
+                -o $out/${config.boot.uki.name}_${config.system.image.version}.img.zst
             '';
 
         # Prepare a ready-to-boot disk image.
@@ -56,20 +59,27 @@
           pkgs.runCommand "update-${config.system.image.version}"
             {
               nativeBuildInputs = with pkgs; [
-                erofs-utils
                 qemu
+                zstd
               ];
             }
             ''
               mkdir -p $out
+              cp ${config.system.build.image}/${config.boot.uki.name}_${config.system.image.version}.raw $out/
               qemu-img convert -f raw -O qcow2 -C ${config.system.build.image}/${config.boot.uki.name}_${config.system.image.version}.raw $out/disk.qcow2
+
+              zstd -9 ${config.system.build.image}/${config.boot.uki.name}_${config.system.image.version}.store.raw \
+                -o $out/${config.boot.uki.name}_${config.system.image.version}.img.zst
+
+              zstd -9 ${config.system.build.uki}/${config.system.boot.loader.ukiFile} \
+                -o $out/${config.system.boot.loader.ukiFile}.zst
             '';
       in
       {
         devShell = pkgs.mkShell {
-          packages = [
-            pkgs.erofs-utils
-            pkgs.just
+          packages = with pkgs; [
+            erofs-utils
+            just
             self.packages.${system}.qemu-efi
           ];
         };
@@ -79,6 +89,8 @@
           patos_image = mkInstallImage self.nixosConfigurations.${system}.patos;
           patos_update = mkUpdate self.nixosConfigurations.${system}.patos;
 
+          image = system.build;
+
           # FIXME: only do for x86_64
           # A helper script to run the disk images above.
           qemu-efi = pkgs.writeShellApplication {
@@ -88,7 +100,7 @@
 
             text = ''
               qemu-system-x86_64 \
-                -smp 2 -m 2048 -machine q35,accel=kvm \
+                -smp 4 -m 2048 -machine q35,accel=kvm \
                 -bios ${pkgs.OVMF.fd}/FV/OVMF.fd \
                 -snapshot \
                 -display none \

justfile

@@ -15,6 +15,10 @@ build: build-image
 build-image:
   nix build .#patos_image
 
+# Build PatOS update image
+build-update:
+  nix build .#patos_update
+
 run: build-image
   qemu-efi -hda ./result/disk.qcow2
   

modules/generic.nix

@@ -9,6 +9,7 @@
   boot = {
     enableContainers = false;
     initrd.systemd.enable = true;
+    initrd.compressor = "zstd";
     kernelParams = [
       "console=ttyS0"
     ];

modules/minimize.nix

@@ -7,11 +7,12 @@
   nix.enable = false;
   system.disableInstallerTools = true;
   system.etc.overlay.enable = true;
-
   systemd.sysusers.enable = true;
 
   programs.less.lessopen = null;
   programs.command-not-found.enable = false;
 
   environment.defaultPackages = [ ];
+
+  security.sudo.enable = false;
 }

modules/partitions.nix

@@ -21,10 +21,13 @@
 
       mkfsOptions = {
         erofs = [
-          "-zzstd,6" # Zstd compression
+          # "-zzstd,6" # Zstd compression
+          # "-zlz4hc,12"
           "-T0" # Fixed timestamp for all files
-          "-C65536" # 64 KiB cluster size
-          # "-Efragments,dedupe,ztailpacking" # Extra features
+          "-C262144" # 256 KiB cluster size
+          # "-C65536" # 64 KiB cluster size
+          # "-C1048576" # 1 MiB cluster size
+          "-Efragments,dedupe,ztailpacking" # Extra features
         ];
       };
 

overlays/default.nix

@@ -7,4 +7,13 @@ final: prev: {
       "--enable-zstd"
     ];
   });
+
+  util-linux = prev.util-linux.override {
+    ncursesSupport = false;
+    nlsSupport = false;
+  };
+
+  dbus = prev.dbus.override {
+    x11Support = false;
+  };
 }