many performance optimizations

modules/sys/perf.nix

@@ -8,17 +8,45 @@
     };
   };
   services.fstrim.enable = true;
-  services.system76-scheduler.enable = true;
-  #services.thermald.enable = true;
+  services.system76-scheduler = {
+    enable = true;
+    settings = {
+      processScheduler = {
+        foregroundBoost = {
+          #background = {
+          #  ioClass = "idle";
+          #};
+          foreground = {
+            ioClass = "realtime";
+            class = "fifo";
+          };
+        };
+        pipewireBoost.profile = {
+          ioClass = "realtime";
+          class = "fifo";
+        };
+      };
+    };
+  };
   services.power-profiles-daemon.enable = true;
-  systemd.coredump.enable = false;
+  systemd.coredump = { # https://discourse.nixos.org/t/how-to-completely-disable-coredump/77335/11
+    enable = true;
+    settings.Coredump = {
+      Storage = "none";
+      ProcessSizeMax = "0";
+  };
   zramSwap = {
     enable = true;
     algorithm = "zstd";
     memoryPercent = 90;
   };
-  services.udev.extraRules = ''
-  ACTION=="add|change", KERNEL=="nvme[0-9]*", ATTR{queue/scheduler}="kyber"
-  ACTION=="add|change", KERNEL=="sd[a-z]", ATTR{queue/rotational}=="0", ATTR{queue/scheduler}="kyber"
-  '';
-}
+  hardware.block.scheduler = {
+    "mmcblk[0-9]*" = "bfq";
+    "nvme[0-9]*"   = "kyber";
+    "sd[a-z]"      = "kyber";
+  };
+  services.scx = {
+    enable = true;
+    scheduler = "scx_cake";
+  };
+}