perf(app): skip unchanged software web frames

crates/ely_app/src/shell/gpui_harness_tests.rs

@@ -1033,6 +1033,7 @@ fn identical_live_frames_share_render_image_arc() -> Result<(), String> {
         Arc::as_ptr(first_image),
         Arc::as_ptr(second_image),
     );
+    assert!(first.has_same_software_render_as(&second));
     Ok(())
 }
 

crates/ely_app/src/shell/web_surface.rs

@@ -6,17 +6,17 @@ use gpui::{Bounds, Pixels, Point};
 
 use crate::services::ProfileDataMode;
 
-use super::web_surface_metadata::WebSurfacePageMetadata;
 use super::{
     web_surface_cadence::IDLE_POLL_INTERVAL,
     web_surface_frame::WebSurfaceFrame,
     web_surface_geometry::{WebSurfaceClickPoint, WebSurfaceScrollDelta, WebSurfaceSize},
+    web_surface_metadata::WebSurfacePageMetadata,
     web_surface_permissions::WebSurfaceSitePermission,
-    web_surface_runtime::{WebSurfaceRuntime, WebSurfaceRuntimeFrame, WebSurfaceUrlChange},
+    web_surface_runtime::{WebSurfaceRuntime, WebSurfaceRuntimeFrame},
     web_surface_state::{
         PerTabSurface, WebSurfaceClickState, WebSurfaceEnsureKey, WebSurfaceInputOutcome,
         WebSurfaceKeyboardFocusState, WebSurfacePendingInput, WebSurfaceScrollState,
-        WebSurfaceState, WebSurfaceTextInputState,
+        WebSurfaceState, WebSurfaceTextInputState, WebSurfaceTickResult,
     },
 };
 
@@ -118,14 +118,18 @@ impl WebSurfaceStore {
                         }
                         continue;
                     }
-                    if let Some(metadata) = WebSurfacePageMetadata::from_frame(&tab_id, &frame) {
+                    result
-                        result.page_metadata.push(metadata);
+                        .page_metadata
-                    }
+                        .extend(WebSurfacePageMetadata::from_frame(&tab_id, &frame));
+                    if self
+                        .surfaces
+                        .get(&tab_id)
+                        .is_none_or(|surface| !surface.matches_ready(&frame))
+                    {
                         self.surface_mut(&tab_id).state = Some(WebSurfaceState::Ready(*frame));
                         result.changed = true;
-                    if let Some(url_change) = url_change {
-                        result.url_changes.push(url_change);
                     }
+                    result.url_changes.extend(url_change);
                 }
                 WebSurfaceRuntimeFrame::Failed { tab_id, message } => {
                     let had_ready = matches!(
@@ -483,13 +487,6 @@ pub(super) fn is_external_web_url(url: &str) -> bool {
     url.starts_with("https://") || url.starts_with("http://")
 }
 
-#[derive(Default)]
-pub(super) struct WebSurfaceTickResult {
-    pub(super) changed: bool,
-    pub(super) url_changes: Vec<WebSurfaceUrlChange>,
-    pub(super) page_metadata: Vec<WebSurfacePageMetadata>,
-}
-
 #[cfg(test)]
 #[path = "web_surface_tests.rs"]
 mod tests;

crates/ely_app/src/shell/web_surface_frame.rs

@@ -14,24 +14,9 @@ use thiserror::Error;
 use crate::services::servo_live::ServoLiveFrame;
 
 thread_local! {
-    /// Single-slot cache of the most-recently-uploaded RGBA payload.
+    /// Single-slot cache for byte-identical software frames.
-    /// At 60 fps on a 1080p canvas the previous `from_parts` was
+    /// AHash keeps the 1080p hash pass below the frame budget while
-    /// unconditionally building a fresh `Arc<RenderImage>` for every
+    /// avoiding repeated GPUI texture allocation for idle pages.
-    /// tick — even when the bytes were bit-identical to the last
-    /// frame. The cache keys on a 64-bit hash of the raw bytes and
-    /// reuses the existing `Arc<RenderImage>` whenever the hash
-    /// matches, so steady-state idle pages no longer churn the GPUI
-    /// texture pool.
-    ///
-    /// Uses `AHasher` instead of std's `DefaultHasher`. SipHash13
-    /// (default) tops out around ~1.5 GB/s; an 8 MB 1080p frame
-    /// hashes in ~5 ms on a modern CPU, which eats roughly 30 % of
-    /// the 16 ms scroll budget on every cache-miss frame. AHash
-    /// runs ~10 GB/s on the same hardware, dropping the per-frame
-    /// hash cost to ~0.8 ms and giving the scroll path back most of
-    /// that budget. Hash collisions remain ~1 in 2^64; if they ever
-    /// matter we'll trade in length + first/last 32 bytes as a
-    /// disambiguator before paying the full memcmp.
     static LAST_FRAME_IMAGE: RefCell<Option<(u64, Arc<RenderImage>)>> =
         const { RefCell::new(None) };
 }
@@ -62,12 +47,9 @@ pub(super) struct WebSurfaceFrame {
     content_pixel_count: u64,
     #[cfg(all(test, feature = "live-site-smoke"))]
     sample_hash: u64,
-    /// Software-path image built from RGBA bytes when the sidecar runs
+    /// Software-path image built from RGBA bytes.
-    /// without hardware surface publication.
     pub(super) image: Option<Arc<RenderImage>>,
-    /// Hardware-path surface imported from the sidecar's IOSurface.
+    /// Hardware-path IOSurface imported from the sidecar.
-    /// GPUI is patched locally to present BGRA CVPixelBuffers through
-    /// `surface(...)`, so hardware frames can skip the RGBA pipe.
     #[cfg(target_os = "macos")]
     pub(super) pixel_buffer: Option<CVPixelBuffer>,
 }
@@ -231,10 +213,33 @@ impl WebSurfaceFrame {
         self.title.as_deref()
     }
 
+    pub(super) fn has_same_software_render_as(&self, other: &Self) -> bool {
+        #[cfg(target_os = "macos")]
+        if self.pixel_buffer.is_some() || other.pixel_buffer.is_some() {
+            return false;
+        }
+        let (Some(image), Some(other_image)) = (self.image.as_ref(), other.image.as_ref()) else {
+            return false;
+        };
+
+        Arc::ptr_eq(image, other_image)
+            && self.requested_url == other.requested_url
+            && self.loaded_url == other.loaded_url
+            && self.title == other.title
+            && self.render_state == other.render_state
+            && self.width == other.width
+            && self.height == other.height
+            && self.device_pixel_ratio == other.device_pixel_ratio
+            && self.css_viewport_width == other.css_viewport_width
+            && self.css_viewport_height == other.css_viewport_height
+            && self.scroll_offset == other.scroll_offset
+            && self.zoom_percent == other.zoom_percent
+            && self.click_point == other.click_point
+            && self.typed_text == other.typed_text
+    }
+
     pub(super) fn has_visible_content_for_initial_display(&self) -> Result<bool, WebSurfaceError> {
-        // The sidecar suppresses blank initial hardware frames with readback
+        // Sidecar readback suppresses blank initial frames before publication.
-        // sampling before sending them. Keep this app-side gate metadata-only
-        // so GPUI's update path never locks or scans IOSurface memory.
         #[cfg(all(test, feature = "live-site-smoke"))]
         {
             Ok(self.non_white_pixel_count > 0 && self.content_pixel_count > 0)

crates/ely_app/src/shell/web_surface_runtime_tests.rs

@@ -26,6 +26,7 @@ static FAKE_ENSURE_COUNT: AtomicUsize = AtomicUsize::new(0);
 static IDLE_SKIP_ENSURE_COUNT: AtomicUsize = AtomicUsize::new(0);
 static RECOVERY_FACTORY_COUNT: AtomicUsize = AtomicUsize::new(0);
 static FAILING_ENSURE_COUNT: AtomicUsize = AtomicUsize::new(0);
+static REPEATED_FRAME_ENSURE_COUNT: AtomicUsize = AtomicUsize::new(0);
 
 #[test]
 fn runtime_keeps_independent_clients_for_profile_scopes() -> Result<(), String> {
@@ -137,6 +138,48 @@ fn store_tick_delay_tracks_runtime_cadence() -> Result<(), String> {
     Ok(())
 }
 
+#[test]
+fn identical_ready_software_frame_keeps_tick_unchanged() -> Result<(), String> {
+    REPEATED_FRAME_ENSURE_COUNT.store(0, Ordering::SeqCst);
+    let mut store = WebSurfaceStore::new_with_runtime(WebSurfaceRuntime::new_with_client_factory(
+        repeated_frame_client_factory,
+    ));
+    let tab = web_tab(TabId::new(), ProfileId::new(), "https://example.com/repeated")?;
+    let visible_tabs = vec![tab.id().clone()];
+
+    assert_eq!(
+        store.record_viewport_size(tab.id(), viewport_bounds(), 1.0),
+        WebSurfaceInputOutcome::Applied,
+    );
+    assert!(store.ensure_surface(&tab, ProfileDataMode::Transient, &[]));
+    store.flush_runtime_for_test();
+    let first_tick = store.tick(&visible_tabs);
+
+    assert!(first_tick.changed);
+    assert_eq!(first_tick.page_metadata.len(), 1);
+    assert_eq!(first_tick.url_changes.len(), 1);
+    assert_eq!(REPEATED_FRAME_ENSURE_COUNT.load(Ordering::SeqCst), 1);
+
+    assert_eq!(
+        store.record_click_point(
+            tab.id(),
+            tab.url().as_str(),
+            gpui::point(gpui::px(10.0), gpui::px(10.0)),
+            1.0,
+        ),
+        WebSurfaceInputOutcome::Applied,
+    );
+    let _ = store.ensure_surface(&tab, ProfileDataMode::Transient, &[]);
+    store.flush_runtime_for_test();
+    let second_tick = store.tick(&visible_tabs);
+
+    assert!(!second_tick.changed);
+    assert_eq!(second_tick.page_metadata.len(), 1);
+    assert_eq!(second_tick.url_changes.len(), 1);
+    assert_eq!(REPEATED_FRAME_ENSURE_COUNT.load(Ordering::SeqCst), 2);
+    Ok(())
+}
+
 #[test]
 fn sidecar_exit_removes_dead_runtime_client() -> Result<(), String> {
     RECOVERY_FACTORY_COUNT.store(0, Ordering::SeqCst);
@@ -238,6 +281,7 @@ struct FakeLiveRuntimeClient;
 struct IdleSkipLiveRuntimeClient;
 struct SidecarExitLiveRuntimeClient;
 struct FailingLiveRuntimeClient;
+struct RepeatedFrameLiveRuntimeClient;
 
 impl LiveRuntimeClient for FakeLiveRuntimeClient {
     fn ensure(
@@ -311,6 +355,24 @@ impl LiveRuntimeClient for FailingLiveRuntimeClient {
     }
 }
 
+impl LiveRuntimeClient for RepeatedFrameLiveRuntimeClient {
+    fn ensure(
+        &mut self,
+        _request: ServoLiveEnsureRequest,
+    ) -> Result<Option<ServoLiveFrame>, LiveRuntimeClientError> {
+        REPEATED_FRAME_ENSURE_COUNT.fetch_add(1, Ordering::SeqCst);
+        Ok(Some(repeated_live_frame()))
+    }
+
+    fn poll(&mut self, _tab_id: String) -> Result<Option<ServoLiveFrame>, LiveRuntimeClientError> {
+        Ok(None)
+    }
+
+    fn close(&mut self, _tab_id: String) -> Result<(), LiveRuntimeClientError> {
+        Ok(())
+    }
+}
+
 fn fake_client_factory(
     _config_dir: std::path::PathBuf,
 ) -> Result<Box<dyn LiveRuntimeClient>, String> {
@@ -339,6 +401,16 @@ fn failing_client_factory(
     Ok(Box::new(FailingLiveRuntimeClient))
 }
 
+fn repeated_frame_client_factory(
+    _config_dir: std::path::PathBuf,
+) -> Result<Box<dyn LiveRuntimeClient>, String> {
+    Ok(Box::new(RepeatedFrameLiveRuntimeClient))
+}
+
+fn repeated_live_frame() -> ServoLiveFrame {
+    ServoLiveFrame::for_test(1, 1, vec![16, 32, 64, 255])
+}
+
 fn web_tab(tab_id: TabId, profile_id: ProfileId, url: &str) -> Result<BrowserTab, String> {
     let url = UrlText::parse(url).map_err(|error| error.to_string())?;
     Ok(BrowserTab::new(tab_id, SpaceId::new(), profile_id, "Web", url))

crates/ely_app/src/shell/web_surface_state.rs

@@ -9,7 +9,9 @@ use super::{
     web_surface_geometry::{
         WebSurfaceClickPoint, WebSurfaceScrollDelta, WebSurfaceScrollOffset, WebSurfaceSize,
     },
+    web_surface_metadata::WebSurfacePageMetadata,
     web_surface_permissions::WebSurfaceSitePermission,
+    web_surface_runtime::WebSurfaceUrlChange,
 };
 
 pub(super) struct WebSurfaceScrollState {
@@ -101,6 +103,13 @@ pub(super) enum WebSurfaceState {
     Failed { message: String },
 }
 
+#[derive(Default)]
+pub(super) struct WebSurfaceTickResult {
+    pub(super) changed: bool,
+    pub(super) url_changes: Vec<WebSurfaceUrlChange>,
+    pub(super) page_metadata: Vec<WebSurfacePageMetadata>,
+}
+
 /// All per-tab surface invariants in one owner.
 ///
 /// Replaces the previous 11 parallel `BTreeMap<TabId, _>` fields on
@@ -179,6 +188,13 @@ impl PerTabSurface {
         self.last_ensure_key = Some(key);
     }
 
+    pub(super) fn matches_ready(&self, frame: &WebSurfaceFrame) -> bool {
+        match self.state.as_ref() {
+            Some(WebSurfaceState::Ready(current)) => current.has_same_software_render_as(frame),
+            _ => false,
+        }
+    }
+
     fn has_pending_input(&self) -> bool {
         self.hover_point.is_some()
             || self.click_point.is_some()