feat: nb performance tweaks

hosts/nb/configuration.nix

@@ -77,9 +77,17 @@ in {
 
   swapDevices = [ {
     device = "/nix/persist/swapfile";
-    size = 32 * 1024;  # Size is in megabytes
+    size = 32 * 1024;  # Size is in megabytes (for hibernation)
   } ];
 
+  # Memory tuning for 92GB RAM
+  boot.kernel.sysctl = {
+    "vm.swappiness" = 10;
+    "vm.dirty_ratio" = 10;
+    "vm.dirty_background_ratio" = 5;
+    "vm.vfs_cache_pressure" = 50;
+  };
+
   # nixos cross building qemu
   boot.binfmt.emulatedSystems = [ "aarch64-linux" ];
   boot.supportedFilesystems = [ "ntfs" ];
@@ -100,18 +108,6 @@ in {
     General = { ControllerMode = "bredr"; };
   };
 
-  services.tlp = {
-    enable = true;
-    settings = {
-      CPU_SCALING_GOVERNOR_ON_AC = "performance";
-      CPU_SCALING_GOVERNOR_ON_BAT = "powersave";
-      CPU_ENERGY_PERF_POLICY_ON_BAT = "power";
-      CPU_ENERGY_PERF_POLICY_ON_AC = "performance";
-      START_CHARGE_THRESH_BAT0 = 60;
-      STOP_CHARGE_THRESH_BAT0 = 80;
-    };
-  };
-
   environment.persistence."/nix/persist" = {
     hideMounts = true;
     directories = [
@@ -263,13 +259,16 @@ in {
   };
 
   nix = {
-    settings.auto-optimise-store = true;
-    settings.experimental-features = [ "nix-command" "flakes" ];
-    # autoOptimiseStore = true;
+    settings = {
+      auto-optimise-store = true;
+      experimental-features = [ "nix-command" "flakes" ];
+      max-jobs = 12;
+      cores = 2;
+    };
     gc = {
       automatic = true;
-      dates = "daily";
-      options = "--delete-older-than 30d";
+      dates = "weekly";
+      options = "--delete-older-than 14d";
     };
     # Free up to 1GiB whenever there is less than 100MiB left.
     extraOptions = ''