scheduler: fix scheduler not working, prioritize foreground

Signed-off-by: Kajus Naujokaitis <[email protected]>

Author: kajusnau

REUSE.toml

@@ -31,7 +31,8 @@ path = [
   "overlays/custom-packages/cosmic/cosmic-comp/0001-Disable-VRR-by-default.patch",
   "overlays/custom-packages/cosmic/cosmic-initial-setup/0001-Preselect-Ghaf-themes.patch",
   "overlays/custom-packages/cosmic/cosmic-greeter/0001-Replace-fallback-background-with-Ghaf-default.patch",
-  "overlays/custom-packages/cosmic/cosmic-applets/*.patch"
+  "overlays/custom-packages/cosmic/cosmic-applets/*.patch",
+  "overlays/custom-packages/system76-scheduler/0001-fix-add-missing-loop-in-process-scheduler-refresh-ta.patch"
 ]
 
 [[annotations]]

modules/common/services/performance/guests.nix

@@ -53,24 +53,36 @@ let
       matchers = [
         "pipewire"
         "pipewire-pulse"
+        "wireplumber"
+      ];
+    };
+    # Apps belonging to user
+    # Minor prioritization
+    # Should be removed when cosmic-comp supports foreground checking
+    app-slice = {
+      nice = -2;
+      ioClass = "best-effort";
+      ioPrio = 0;
+      matchers = [
+        "include cgroup=\"/user.slice/*slice/*service/*slice/*.scope\""
       ];
     };
     # Session services belonging to the user
     session-services = {
-      nice = 12;
+      nice = 9;
       ioClass = "idle";
       matchers = [
-        "include cgroup=\"/user.slice/*.service\" parent=\"systemd\""
-        "include cgroup=\"/user.slice/*.session.slice/*\" parent=\"systemd\""
-        "include cgroup=\"/user.slice/*app-dbus*\""
+        "include cgroup=\"/user.slice/*.slice/*\""
+        "exclude cgroup=\"/user.slice/*.slice/*.service/app.slice/*\""
       ];
     };
     # System services belonging to root
     system-services = {
-      nice = 15;
+      nice = 12;
       ioClass = "idle";
       matchers = [
         "include cgroup=\"/system.slice/*\""
+        "exclude cgroup=\"/user.slice/*\" parent=\"systemd\""
       ];
     };
   };
@@ -182,11 +194,7 @@ in
     };
 
     net = {
-      enable = mkEnableOption "Ghaf-specific scheduler and power optimizations for net-vm.";
-      scheduler = {
-        # net-vm is running on one core, so scheduling is too heavy for it to be useful
-        enable = mkEnableOption "system76-scheduler on net-vm for Ghaf-specific process scheduling.";
-      };
+      enable = mkEnableOption "Ghaf-specific power optimizations for net-vm.";
       tuned = {
         enable = mkEnableOption "TuneD service on the net-vm for Ghaf-specific performance profiles." // {
           default = true;
@@ -215,8 +223,13 @@ in
         inherit (cfg.gui.scheduler) enable;
         settings = {
           processScheduler = {
-            pipewireBoost.enable = true;
+            pipewireBoost.enable = false;
+            # cosmic-comp still lacks integration with s76-scheduler
+            foregroundBoost.enable = false;
+            useExecsnoop = true;
+            refreshInterval = 30;
           };
+          cfsProfiles.enable = false;
         };
         assignments = guiVmSchedulerAssignments;
       };
@@ -267,15 +280,6 @@ in
 
     (mkIf cfg.net.enable (
       {
-        services.system76-scheduler = {
-          inherit (cfg.net.scheduler) enable;
-          settings = {
-            processScheduler = {
-              # Instead poll every 60s
-              useExecsnoop = false;
-            };
-          };
-        };
         services.tuned = {
           inherit (cfg.net.tuned) enable;
           ppdSupport = true;

modules/common/services/performance/host.nix

@@ -45,6 +45,8 @@ let
       ioClass = "idle";
       matchers = [
         "include cgroup=\"/system.slice/*\""
+        "exclude cgroup=\"/system.slice/system-sysvms.slice/*\""
+        "exclude cgroup=\"/system.slice/system-appvms.slice/*\""
       ];
     };
   };
@@ -170,7 +172,6 @@ let
       sysctl = {
         "vm.swappiness" = "20";
         "vm.dirty_writeback_centisecs" = "1500";
-        "kernel.sched_autogroup_enabled" = "1";
         "vm.laptop_mode" = "2";
       };
     };
@@ -241,6 +242,8 @@ in
           settings = {
             cfsProfiles.enable = false;
             processScheduler = {
+              useExecsnoop = true;
+              refreshInterval = 60;
               pipewireBoost.enable = false;
               foregroundBoost.enable = false;
             };

modules/microvm/sysvms/guivm.nix

@@ -214,6 +214,7 @@ let
                 pkgs.waypipe
                 pkgs.gnome-calculator
                 pkgs.sticky-notes
+                pkgs.tuned
               ])
               ++ [
                 pkgs.pamixer

overlays/custom-packages/default.nix

@@ -20,6 +20,7 @@
   libfm = import ./libfm { inherit prev; };
   papirus-icon-theme = import ./papirus-icon-theme { inherit prev; };
   qemu_kvm = import ./qemu { inherit final prev; };
+  system76-scheduler = import ./system76-scheduler { inherit prev; };
   tpm2-pkcs11 = import ./tpm2-pkcs11 { inherit prev; };
   tpm2-tools = import ./tpm2-tools { inherit prev; };
   xdg-desktop-portal-cosmic = import ./cosmic/xdg-desktop-portal-cosmic { inherit prev; };

overlays/custom-packages/system76-scheduler/0001-fix-add-missing-loop-in-process-scheduler-refresh-ta.patch

@@ -0,0 +1,31 @@
+From eddba4de430f72117f9557e8a0ed2efebbb1ca36 Mon Sep 17 00:00:00 2001
+From: Kajus Naujokaitis <[email protected]>
+Date: Mon, 24 Nov 2025 16:20:36 +0200
+Subject: [PATCH] fix: add missing loop in process scheduler refresh task
+
+Signed-off-by: Kajus Naujokaitis <[email protected]>
+---
+ daemon/src/main.rs | 7 +++++--
+ 1 file changed, 5 insertions(+), 2 deletions(-)
+
+diff --git a/daemon/src/main.rs b/daemon/src/main.rs
+index 308f069..7124ae7 100644
+--- a/daemon/src/main.rs
++++ b/daemon/src/main.rs
+@@ -189,8 +189,11 @@ async fn daemon(
+                 Duration::from_secs(u64::from(service.config.process_scheduler.refresh_rate));
+             let tx = tx.clone();
+             async move {
+-                let _res = tx.send(Event::RefreshProcessMap).await;
+-                tokio::time::sleep(refresh_rate).await;
++                let mut interval = tokio::time::interval(refresh_rate);
++                loop {
++                    interval.tick().await;
++                    let _ = tx.send(Event::RefreshProcessMap).await;
++                }
+             }
+         });
+ 
+-- 
+2.51.2
+

overlays/custom-packages/system76-scheduler/default.nix

@@ -0,0 +1,7 @@
+# SPDX-FileCopyrightText: 2022-2026 TII (SSRC) and the Ghaf contributors
+# SPDX-License-Identifier: Apache-2.0
+{ prev }:
+
+prev.system76-scheduler.overrideAttrs (_old: {
+  patches = [ ./0001-fix-add-missing-loop-in-process-scheduler-refresh-ta.patch ];
+})