desktop: zfs with old drives

etcnixos/system-yarn.nix

@@ -17,18 +17,31 @@
     inputs.nixos-hardware.nixosModules.common-cpu-amd-zenpower
   ];
 
+  networking.hostId = "abf570f9";
   boot = {
+    kernelPackages = lib.mkForce pkgs.linuxPackages;
+
     kernelParams = [
       # allow overclocking (I actually underclock but lol)
       "amdgpu.ppfeaturemask=0xFFF7FFFF"
+
+      # 2048MB
+      "zfs.zfs_arc_max=2048000000"
     ];
 
+    supportedFilesystems = [ "zfs" ];
+    zfs.extraPools = [ "laptop_hdds" ];
+
     kernelModules = [
       # kernel module for case fan control
       "nct6775"
     ];
   };
 
+  systemd.tmpfiles.rules = [
+    "d /laptop_hdds 0755 ${username} users"
+  ];
+
   services.xserver.enable = false;
   services.desktopManager.plasma6.enable = true;
   services.displayManager = {