From d4a6f228c0cb8012795c496ff14aefaa35898ff8 Mon Sep 17 00:00:00 2001
From: caandt <caandt@twoha.cc>
Date: Mon, 5 Jan 2026 01:53:38 -0600
Subject: [PATCH] virt

---
 hosts/tachibana/virt.nix | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/hosts/tachibana/virt.nix b/hosts/tachibana/virt.nix
index 73cc589..cb40a50 100644
--- a/hosts/tachibana/virt.nix
+++ b/hosts/tachibana/virt.nix
@@ -22,10 +22,29 @@
     extraModprobeConfig = ''
       options vfio-pci ids=10de:2b85,10de:22e8
       options kvmfr static_size_mb=64
+      options kvm_amd avic=1
     '';
   };
   services.udev.extraRules = ''
     SUBSYSTEM=="kvmfr", GROUP="kvm", MODE="0660"
   '';
   environment.systemPackages = [pkgs.looking-glass-client];
+  virtualisation.libvirtd.hooks.qemu = {
+    "isolatecpu.sh" =
+      pkgs.writeShellScript "isolatecpu.sh"
+      ''
+        #!/bin/sh
+        PIN="AllowedCPUs=8-15,24-31"
+        ALL="AllowedCPUs=0-31"
+        if [ "$2" = "started" ]; then
+          systemctl set-property --runtime -- system.slice $PIN
+          systemctl set-property --runtime -- user.slice $PIN
+          systemctl set-property --runtime -- init.scope $PIN
+        elif [ "$2" = "release" ]; then
+          systemctl set-property --runtime -- system.slice $ALL
+          systemctl set-property --runtime -- user.slice $ALL
+          systemctl set-property --runtime -- init.scope $ALL
+        fi
+      '';
+  };
 }