From 553c6d609d2e7ea169769d566d9a58ed0322e583 Mon Sep 17 00:00:00 2001
From: chn <chn@chn.moe>
Date: Mon, 19 Jun 2023 14:40:12 +0800
Subject: [PATCH] use bfq

---
 modules/boot/chn-PC.nix       | 8 +++++++-
 modules/filesystem/chn-PC.nix | 2 ++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/modules/boot/chn-PC.nix b/modules/boot/chn-PC.nix
index 59b6658e..25e77f98 100644
--- a/modules/boot/chn-PC.nix
+++ b/modules/boot/chn-PC.nix
@@ -9,7 +9,7 @@
 			# initrd 里有的模块
 			initrd.availableKernelModules =
 			[
-				"ahci" "i915" "intel_cstate" "nls_cp437" "nls_iso8859-1" "nvidia" "nvidia_drm" "nvidia_modeset"
+				"ahci" "bfq" "i915" "intel_cstate" "nls_cp437" "nls_iso8859-1" "nvidia" "nvidia_drm" "nvidia_modeset"
 				"nvidia_uvm" "nvme" "sr_mod" "usbhid" "usb_storage" "virtio_blk" "virtio_pci" "xhci_pci"
 			];
 
@@ -29,5 +29,11 @@
 			resumeDevice = "/dev/mapper/root";
 		};
 		hardware.cpu.intel.updateMicrocode = true;
+
+		services.udev.extraRules =
+		''
+			ACTION=="add|change", KERNEL=="[sv]d[a-z]", ATTR{queue/rotational}=="0", ATTR{queue/scheduler}="bfq"
+			ACTION=="add|change", KERNEL=="nvme[0-9]n[0-9]", ATTR{queue/rotational}=="0", ATTR{queue/scheduler}="bfq"
+		'';
 	};
 }
diff --git a/modules/filesystem/chn-PC.nix b/modules/filesystem/chn-PC.nix
index f2c29115..37e469b5 100644
--- a/modules/filesystem/chn-PC.nix
+++ b/modules/filesystem/chn-PC.nix
@@ -9,6 +9,8 @@
 				fsType = "tmpfs";
 				options = [ "size=16G" "relatime" "mode=755" ];
 			};
+			# disable CoW for VM image and database
+			# sudo chattr +C images
 			"/nix" =
 			{
 				device = "/dev/mapper/root";