athena low latency

artemis.nix

@@ -0,0 +1,10 @@
+{ ... }:
+
+{
+  imports = [
+    ./configuration.nix
+    ./artemis-hardware-configuration.nix
+  ];
+
+  networking.hostName = "artemis";
+}

athena-hardware-configuration.nix

@@ -0,0 +1,31 @@
+# Do not modify this file!  It was generated by ‘nixos-generate-config’
+# and may be overwritten by future invocations.  Please make changes
+# to /etc/nixos/configuration.nix instead.
+{ config, lib, pkgs, modulesPath, ... }:
+
+{
+  imports =
+    [ (modulesPath + "/installer/scan/not-detected.nix")
+    ];
+
+  boot.initrd.availableKernelModules = [ "nvme" "xhci_pci" "ahci" "usbhid" "usb_storage" "sd_mod" ];
+  boot.initrd.kernelModules = [ ];
+  boot.kernelModules = [ ];
+  boot.extraModulePackages = [ ];
+
+  fileSystems."/" =
+    { device = "/dev/disk/by-uuid/c5614bab-0755-48a2-9cb0-0dc31b98371f";
+      fsType = "ext4";
+    };
+
+  fileSystems."/boot" =
+    { device = "/dev/disk/by-uuid/1965-42F3";
+      fsType = "vfat";
+      options = [ "fmask=0077" "dmask=0077" ];
+    };
+
+  swapDevices = [ ];
+
+  nixpkgs.hostPlatform = lib.mkDefault "x86_64-linux";
+  hardware.cpu.amd.updateMicrocode = lib.mkDefault config.hardware.enableRedistributableFirmware;
+}

athena.nix

@@ -0,0 +1,19 @@
+{ ... }:
+
+{
+  imports = [
+    ./configuration.nix
+    ./athena-hardware-configuration.nix
+  ];
+
+  networking.hostName = "athena";
+  
+  services.pipewire.extraConfig.pipewire."10-low-latency" = {
+    "context.properties" = {
+      "default.clock.rate" = 48000;
+      "default.clock.quantum" = 64;
+      "default.clock.min-quantum" = 64;
+      "default.clock.max-quantum" = 64;
+    };
+  };
+}

configuration.nix

@@ -5,19 +5,12 @@
 { config, pkgs, ... }:
 
 {
-  imports =
-    [ # Include the results of the hardware scan.
-      ./hardware-configuration.nix
-    ];
-
   # Bootloader.
   boot.loader.systemd-boot.enable = true;
   boot.loader.efi.canTouchEfiVariables = true;
 
   # Use latest kernel.
   boot.kernelPackages = pkgs.linuxPackages_zen;
-
-  networking.hostName = "artemis"; # Define your hostname.
   networking.wireless.enable = true;  # Enables wireless support via wpa_supplicant.
 
   # Configure network proxy if necessary
@@ -83,22 +76,31 @@
   };
   
   musnix.enable = true;
+  musnix.kernel.realtime = false;   # force non-RT while we tune everything else
+  musnix.rtirq.enable = true;       # IRQ thread priority tuning — helps USB audio specifically
+  musnix.rtirq.nameList = "snd usb"; # prioritize sound + USB IRQs
   
   # realtime audio shenanigans 
   security.pam.loginLimits = [
-  {
-    domain = "@audio";
-    type = "-";
-    item = "rtprio";
-    value = "95";
-  }
-  {
-    domain = "@audio";
-    type = "-";
-    item = "memlock";
-    value = "unlimited";
-  }
-];
+    {
+      domain = "@audio";
+      type = "-";
+      item = "rtprio";
+      value = "95";
+    }
+    {
+      domain = "@audio";
+      type = "-";
+      item = "memlock";
+      value = "unlimited";
+    }
+  ];
+  
+  systemd.user.services.pipewire.serviceConfig.CPUAffinity = "8-15";
+  systemd.user.services.wireplumber.serviceConfig.CPUAffinity = "8-15";
+  systemd.services.rtkit-daemon.serviceConfig.CPUAffinity = "8-15";
+  
+  programs.nix-ld.enable = true;
 
   # Enable touchpad support (enabled default in most desktopManager).
   # services.xserver.libinput.enable = true;
@@ -132,6 +134,8 @@
     hydrapaper
     nextcloud-client
     fastfetch
+    epson-escpr2
+    gnome-tweaks
   ];
   
   nix.settings.experimental-features = [ "nix-command" "flakes" ];
@@ -158,6 +162,9 @@
     })
   ];
   
+  services.udev.extraRules = ''
+    ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="1235", ATTR{power/control}="on"
+  '';
 
   # Enable the OpenSSH daemon.
   # services.openssh.enable = true;

flake.nix

@@ -15,29 +15,43 @@
   outputs = { self, nixpkgs, home-manager, nix-flatpak, musnix, ... }:
     let
       system = "x86_64-linux";
+
+      commonModules = [
+        musnix.nixosModules.musnix
+
+        home-manager.nixosModules.home-manager
+
+        {
+          home-manager.useGlobalPkgs = true;
+          home-manager.useUserPackages = true;
+
+          home-manager.users.cybrneko = { pkgs, ... }: {
+            imports = [
+              nix-flatpak.homeManagerModules.nix-flatpak
+              ./home.nix
+              ./users/cybrneko.nix
+            ];
+          };
+        }
+      ];
     in {
-      nixosConfigurations.nixos = nixpkgs.lib.nixosSystem {
-        inherit system;
+      nixosConfigurations = {
+        artemis = nixpkgs.lib.nixosSystem {
+          inherit system;
 
-        modules = [
-          ./configuration.nix
+          modules = [
+            ./artemis.nix
+          ] ++ commonModules;
+        };
 
-          musnix.nixosModules.musnix
+        athena = nixpkgs.lib.nixosSystem {
+          inherit system;
 
-          home-manager.nixosModules.home-manager
-
-          {
-            home-manager.useGlobalPkgs = true;
-            home-manager.useUserPackages = true;
-            home-manager.users.cybrneko = { pkgs, ... }: {
-              imports = [
-                nix-flatpak.homeManagerModules.nix-flatpak
-                ./home.nix
-                ./users/cybrneko.nix
-              ];
-            }; 
-          }
-        ];
+          modules = [
+            ./athena.nix
+          ] ++ commonModules;
+        };
       };
     };   
 }
+