perf(borders): introduce state snapshot checks

This commit introduce state snapshot checks in the border manager, which
will ensure that we don't even attempt to acquire any mutex locks if the
state hasn't changed.

komorebi/src/border_manager/mod.rs

@@ -21,6 +21,7 @@ use std::sync::Arc;
 use std::sync::OnceLock;
 use windows::Win32::Foundation::HWND;
 
+use crate::ring::Ring;
 use crate::workspace_reconciliator::ALT_TAB_HWND;
 use crate::Colour;
 use crate::Rgb;
@@ -121,18 +122,25 @@ pub fn handle_notifications(wm: Arc<Mutex<WindowManager>>) -> color_eyre::Result
     let receiver = event_rx();
     event_tx().send(Notification)?;
 
-    'receiver: for _ in receiver {
-        let mut borders = BORDER_STATE.lock();
-        let mut borders_monitors = BORDERS_MONITORS.lock();
+    let mut latest_snapshot = Ring::default();
 
+    'receiver: for _ in receiver {
         // Check the wm state every time we receive a notification
         let state = wm.lock();
         let is_paused = state.is_paused;
         let focused_monitor_idx = state.focused_monitor_idx();
-        let monitors = state.monitors.elements().clone();
+        let monitors = state.monitors.clone();
         let pending_move_op = state.pending_move_op;
         drop(state);
 
+        if monitors == latest_snapshot {
+            tracing::trace!("monitor state matches latest snapshot, skipping notification");
+            continue 'receiver;
+        }
+
+        let mut borders = BORDER_STATE.lock();
+        let mut borders_monitors = BORDERS_MONITORS.lock();
+
         // If borders are disabled
         if !BORDER_ENABLED.load_consume()
            // Or if the wm is paused
@@ -149,7 +157,7 @@ pub fn handle_notifications(wm: Arc<Mutex<WindowManager>>) -> color_eyre::Result
             continue 'receiver;
         }
 
-        'monitors: for (monitor_idx, m) in monitors.iter().enumerate() {
+        'monitors: for (monitor_idx, m) in monitors.elements().iter().enumerate() {
             // Only operate on the focused workspace of each monitor
             if let Some(ws) = m.focused_workspace() {
                 // Workspaces with tiling disabled don't have borders
@@ -337,6 +345,8 @@ pub fn handle_notifications(wm: Arc<Mutex<WindowManager>>) -> color_eyre::Result
                 }
             }
         }
+
+        latest_snapshot = monitors;
     }
 
     Ok(())

komorebi/src/monitor.rs

@@ -19,7 +19,16 @@ use crate::ring::Ring;
 use crate::workspace::Workspace;
 
 #[derive(
-    Debug, Clone, Serialize, Deserialize, Getters, CopyGetters, MutGetters, Setters, JsonSchema,
+    Debug,
+    Clone,
+    Serialize,
+    Deserialize,
+    Getters,
+    CopyGetters,
+    MutGetters,
+    Setters,
+    JsonSchema,
+    PartialEq,
 )]
 pub struct Monitor {
     #[getset(get_copy = "pub", set = "pub")]

komorebi/src/ring.rs

@@ -4,7 +4,7 @@ use schemars::JsonSchema;
 use serde::Deserialize;
 use serde::Serialize;
 
-#[derive(Debug, Clone, Serialize, Deserialize, JsonSchema)]
+#[derive(Debug, Clone, Serialize, Deserialize, JsonSchema, PartialEq)]
 pub struct Ring<T> {
     elements: VecDeque<T>,
     focused: usize,

komorebi/src/window.rs

@@ -39,7 +39,7 @@ use crate::PERMAIGNORE_CLASSES;
 use crate::REGEX_IDENTIFIERS;
 use crate::WSL2_UI_PROCESSES;
 
-#[derive(Debug, Default, Clone, Copy, Deserialize, JsonSchema)]
+#[derive(Debug, Default, Clone, Copy, Deserialize, JsonSchema, PartialEq)]
 pub struct Window {
     pub hwnd: isize,
 }

komorebi/src/workspace.rs

@@ -38,7 +38,16 @@ use crate::REMOVE_TITLEBARS;
 
 #[allow(clippy::struct_field_names)]
 #[derive(
-    Debug, Clone, Serialize, Deserialize, Getters, CopyGetters, MutGetters, Setters, JsonSchema,
+    Debug,
+    Clone,
+    Serialize,
+    Deserialize,
+    Getters,
+    CopyGetters,
+    MutGetters,
+    Setters,
+    JsonSchema,
+    PartialEq,
 )]
 pub struct Workspace {
     #[getset(get = "pub", set = "pub")]