From def8d7e2549f2b2eb54d1115833cd814ffb0ba14 Mon Sep 17 00:00:00 2001
From: oxalica <oxalicc@pm.me>
Date: Fri, 3 May 2024 02:27:44 -0400
Subject: [PATCH] nixos/plasma6: add CAP_SYS_NICE for kwin_wayland

This makes kwin_wayland successfully gain SCHED_RR priority, which
significantly improves the rendering lag, ie. cursor movement and
desktop animations, under heavy CPU load like on compilation.
This was already enabled for plasma5 but is not for plasma6 somehow.
---
 nixos/modules/services/desktop-managers/plasma6.nix | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/nixos/modules/services/desktop-managers/plasma6.nix b/nixos/modules/services/desktop-managers/plasma6.nix
index 08507b4d370a..842b0716b928 100644
--- a/nixos/modules/services/desktop-managers/plasma6.nix
+++ b/nixos/modules/services/desktop-managers/plasma6.nix
@@ -286,6 +286,15 @@ in {
       kde-smartcard = lib.mkIf config.security.pam.p11.enable { p11Auth = true; };
     };
 
+    security.wrappers = {
+      kwin_wayland = {
+        owner = "root";
+        group = "root";
+        capabilities = "cap_sys_nice+ep";
+        source = "${lib.getBin pkgs.kdePackages.kwin}/bin/kwin_wayland";
+      };
+    };
+
     programs.dconf.enable = true;
 
     programs.firefox.nativeMessagingHosts.packages = [kdePackages.plasma-browser-integration];