diff --git a/src/renderer/src/components/editor/EditorAutosaveController.tsx b/src/renderer/src/components/editor/EditorAutosaveController.tsx
index fcce2868bb2..0ba4358d7e8 100644
--- a/src/renderer/src/components/editor/EditorAutosaveController.tsx
+++ b/src/renderer/src/components/editor/EditorAutosaveController.tsx
@@ -1,12 +1,13 @@
 import { useEffect } from 'react'
-import { attachAppEditorAutosaveController } from './editor-autosave-controller'
+import { useAppStore } from '@/store'
+import { attachEditorAutosaveController } from './editor-autosave-controller'
 
 export default function EditorAutosaveController(): null {
   useEffect(() => {
     // Why: autosave and quit coordination need to survive editor tab switches,
     // but keeping the full EditorPanel mounted while hidden widened the restart
     // surface too far. Keep only this narrow controller alive between mounts.
-    return attachAppEditorAutosaveController()
+    return attachEditorAutosaveController(useAppStore)
   }, [])
 
   return null
diff --git a/src/renderer/src/components/editor/editor-autosave-controller.test.ts b/src/renderer/src/components/editor/editor-autosave-controller.test.ts
index c5653f68599..b36b5b472e9 100644
--- a/src/renderer/src/components/editor/editor-autosave-controller.test.ts
+++ b/src/renderer/src/components/editor/editor-autosave-controller.test.ts
@@ -193,6 +193,57 @@ describe('attachEditorAutosaveController', () => {
     }
   })
 
+  it('skips the open-file scan for unrelated store mutations', () => {
+    const writeFile = vi.fn().mockResolvedValue(undefined)
+    const eventTarget = new EventTarget()
+    vi.stubGlobal('window', {
+      addEventListener: eventTarget.addEventListener.bind(eventTarget),
+      removeEventListener: eventTarget.removeEventListener.bind(eventTarget),
+      dispatchEvent: eventTarget.dispatchEvent.bind(eventTarget),
+      setTimeout: globalThis.setTimeout.bind(globalThis),
+      clearTimeout: globalThis.clearTimeout.bind(globalThis),
+      api: {
+        fs: {
+          writeFile
+        }
+      }
+    } satisfies WindowStub)
+
+    const store = createEditorStore()
+    store.getState().openFile({
+      filePath: '/repo/file.ts',
+      relativePath: 'file.ts',
+      worktreeId: 'wt-1',
+      language: 'typescript',
+      mode: 'edit'
+    })
+
+    const openFiles = store.getState().openFiles
+    const originalMap = openFiles.map.bind(openFiles)
+    let mapCalls = 0
+    Object.defineProperty(openFiles, 'map', {
+      configurable: true,
+      value: (...args: Parameters<typeof openFiles.map>) => {
+        mapCalls += 1
+        return originalMap(...args)
+      }
+    })
+
+    const cleanup = attachEditorAutosaveController(store)
+    try {
+      expect(mapCalls).toBe(1)
+      mapCalls = 0
+
+      store.setState({ activeWorktreeId: 'wt-2' } as Partial<AppState>)
+      expect(mapCalls).toBe(0)
+
+      store.getState().setEditorDraft('/repo/file.ts', 'edited')
+      expect(mapCalls).toBe(1)
+    } finally {
+      cleanup()
+    }
+  })
+
   it('flushes mounted rich-editor changes before quiescing or direct saves', async () => {
     const writeFile = vi.fn().mockResolvedValue(undefined)
     const eventTarget = new EventTarget()
diff --git a/src/renderer/src/components/editor/editor-autosave-controller.ts b/src/renderer/src/components/editor/editor-autosave-controller.ts
index 7e8a85049d0..1d94c6955ed 100644
--- a/src/renderer/src/components/editor/editor-autosave-controller.ts
+++ b/src/renderer/src/components/editor/editor-autosave-controller.ts
@@ -1,5 +1,4 @@
 import type { StoreApi } from 'zustand'
-import { useAppStore } from '@/store'
 import type { AppState } from '@/store'
 import type { OpenFile } from '@/store/slices/editor'
 import { getConnectionId } from '@/lib/connection-context'
@@ -19,6 +18,11 @@ import {
 } from './editor-autosave'
 import { flushPendingEditorChange } from './editor-pending-flush'
 import { clearSelfWrite, recordSelfWrite } from './editor-self-write-registry'
+import {
+  autosaveSubscriberInputsEqual,
+  getAutosaveSubscriberInputs,
+  getDuplicateDirtySavePaths
+} from './editor-autosave-state-projections'
 import {
   ORCA_EDITOR_SAVE_DIRTY_FILES_EVENT,
   type EditorSaveDirtyFilesDetail
@@ -26,16 +30,6 @@ import {
 
 type AppStoreApi = Pick<StoreApi<AppState>, 'getState' | 'subscribe'>
 
-function getDuplicateDirtySavePaths(files: OpenFile[]): string[] {
-  const counts = new Map<string, number>()
-  for (const file of files) {
-    counts.set(file.filePath, (counts.get(file.filePath) ?? 0) + 1)
-  }
-  return Array.from(counts.entries())
-    .filter(([, count]) => count > 1)
-    .map(([filePath]) => filePath)
-}
-
 export function attachEditorAutosaveController(store: AppStoreApi): () => void {
   const autoSaveTimers = new Map<string, number>()
   const autoSaveScheduledContent = new Map<string, string>()
@@ -319,7 +313,18 @@ export function attachEditorAutosaveController(store: AppStoreApi): () => void {
     state.clearEditorDrafts(matchingFiles.map((file) => file.id))
   }
 
-  const unsubscribe = store.subscribe(syncAutoSave)
+  // Why: the root store subscriber fires for every terminal title/focus tick.
+  // Autosave only reads these four inputs, so skip the open-files scan when
+  // unrelated store slices change.
+  let previousAutosaveInputs = getAutosaveSubscriberInputs(store.getState())
+  const unsubscribe = store.subscribe(() => {
+    const nextAutosaveInputs = getAutosaveSubscriberInputs(store.getState())
+    if (autosaveSubscriberInputsEqual(previousAutosaveInputs, nextAutosaveInputs)) {
+      return
+    }
+    previousAutosaveInputs = nextAutosaveInputs
+    syncAutoSave()
+  })
   syncAutoSave()
 
   window.addEventListener(ORCA_EDITOR_SAVE_DIRTY_FILES_EVENT, handleSaveDirtyFiles as EventListener)
@@ -356,7 +361,3 @@ export function attachEditorAutosaveController(store: AppStoreApi): () => void {
     saveGeneration.clear()
   }
 }
-
-export function attachAppEditorAutosaveController(): () => void {
-  return attachEditorAutosaveController(useAppStore)
-}
diff --git a/src/renderer/src/components/editor/editor-autosave-state-projections.ts b/src/renderer/src/components/editor/editor-autosave-state-projections.ts
new file mode 100644
index 00000000000..55a1525075c
--- /dev/null
+++ b/src/renderer/src/components/editor/editor-autosave-state-projections.ts
@@ -0,0 +1,40 @@
+import type { AppState } from '@/store'
+import type { OpenFile } from '@/store/slices/editor'
+
+export type AutosaveSubscriberInputs = {
+  openFiles: AppState['openFiles']
+  editorDrafts: AppState['editorDrafts']
+  editorAutoSave: boolean | undefined
+  editorAutoSaveDelayMs: number | undefined
+}
+
+export function getAutosaveSubscriberInputs(state: AppState): AutosaveSubscriberInputs {
+  return {
+    openFiles: state.openFiles,
+    editorDrafts: state.editorDrafts,
+    editorAutoSave: state.settings?.editorAutoSave,
+    editorAutoSaveDelayMs: state.settings?.editorAutoSaveDelayMs
+  }
+}
+
+export function autosaveSubscriberInputsEqual(
+  a: AutosaveSubscriberInputs,
+  b: AutosaveSubscriberInputs
+): boolean {
+  return (
+    a.openFiles === b.openFiles &&
+    a.editorDrafts === b.editorDrafts &&
+    a.editorAutoSave === b.editorAutoSave &&
+    a.editorAutoSaveDelayMs === b.editorAutoSaveDelayMs
+  )
+}
+
+export function getDuplicateDirtySavePaths(files: OpenFile[]): string[] {
+  const counts = new Map<string, number>()
+  for (const file of files) {
+    counts.set(file.filePath, (counts.get(file.filePath) ?? 0) + 1)
+  }
+  return Array.from(counts.entries())
+    .filter(([, count]) => count > 1)
+    .map(([filePath]) => filePath)
+}