fix: Reduce unnecessary IPC calls causing UI unresponsiveness (#1542)

## Problem

Excessive IPC calls during boot and redundant re-renders cause the app to become unresponsive.

Closes #1348

## Changes

  1. Add opt-in IPC timing middleware to log call durations during first 15s of boot
  2. Fix markAsViewed re-firing on every render by stabilizing the dependency to a string key instead of a new array reference
  3. Dedupe recordActivity mutation calls per task run using a module-level Set

## How did you test this?

Manually

Author: charlesvien

apps/code/src/main/trpc/trpc.ts

@@ -1,4 +1,5 @@
 import { initTRPC } from "@trpc/server";
+import log from "electron-log/main";
 
 const trpc = initTRPC.create({
   isServer: true,
@@ -9,28 +10,49 @@ const CALL_RATE_THRESHOLD = 50;
 
 const callCounts: Record<string, number[]> = {};
 
-const callRateMonitor = trpc.middleware(async ({ path, next }) => {
-  if (process.env.NODE_ENV !== "development") {
-    return next();
-  }
+const ipcTimingEnabled = process.env.IPC_TIMINGS === "true";
+const ipcTimingBootMs = 15_000;
+const bootTime = Date.now();
 
-  const now = Date.now();
-  if (!callCounts[path]) {
-    callCounts[path] = [];
-  }
+const callRateMonitor = trpc.middleware(async ({ path, next, type }) => {
+  const shouldTime =
+    ipcTimingEnabled && Date.now() - bootTime < ipcTimingBootMs;
+  const t = shouldTime ? performance.now() : 0;
 
-  const timestamps = callCounts[path];
-  timestamps.push(now);
+  if (shouldTime) {
+    log.info(`[ipc-timing] >> ${type} ${path}`);
+  }
 
-  const cutoff = now - CALL_RATE_WINDOW_MS;
-  while (timestamps.length > 0 && timestamps[0] < cutoff) {
-    timestamps.shift();
+  if (process.env.NODE_ENV === "development") {
+    const now = Date.now();
+    if (!callCounts[path]) {
+      callCounts[path] = [];
+    }
+
+    const timestamps = callCounts[path];
+    timestamps.push(now);
+
+    const cutoff = now - CALL_RATE_WINDOW_MS;
+    while (timestamps.length > 0 && timestamps[0] < cutoff) {
+      timestamps.shift();
+    }
+
+    if (timestamps.length >= CALL_RATE_THRESHOLD) {
+      log.warn(
+        `[ipc-rate] ${type} ${path} called ${timestamps.length} times in ${CALL_RATE_WINDOW_MS}ms`,
+      );
+    }
   }
 
-  if (timestamps.length >= CALL_RATE_THRESHOLD) {
+  const result = await next();
+
+  if (shouldTime) {
+    log.info(
+      `[ipc-timing] << ${type} ${path}: ${(performance.now() - t).toFixed(0)}ms`,
+    );
   }
 
-  return next();
+  return result;
 });
 
 export const router = trpc.router;

apps/code/src/renderer/features/command-center/components/CommandCenterView.tsx

@@ -13,16 +13,17 @@ export function CommandCenterView() {
   const { cells, summary } = useCommandCenterData();
   const { markAsViewed } = useTaskViewed();
 
-  const visibleTaskIds = useMemo(
-    () => cells.map((c) => c.taskId).filter((id): id is string => id != null),
-    [cells],
-  );
+  const visibleTaskIdsKey = cells
+    .map((c) => c.taskId)
+    .filter(Boolean)
+    .join(",");
 
   useEffect(() => {
-    for (const taskId of visibleTaskIds) {
+    if (!visibleTaskIdsKey) return;
+    for (const taskId of visibleTaskIdsKey.split(",")) {
       markAsViewed(taskId);
     }
-  }, [visibleTaskIds, markAsViewed]);
+  }, [visibleTaskIdsKey, markAsViewed]);
 
   const headerContent = useMemo(
     () => (

apps/code/src/renderer/features/sessions/hooks/useSessionConnection.ts

@@ -11,6 +11,7 @@ import { useChatTitleGenerator } from "./useChatTitleGenerator";
 const log = logger.scope("session-connection");
 
 const connectingTasks = new Set<string>();
+const activityRecorded = new Set<string>();
 
 interface UseSessionConnectionOptions {
   taskId: string;
@@ -37,14 +38,20 @@ export function useSessionConnection({
   useEffect(() => {
     const taskRunId = session?.taskRunId;
     if (!taskRunId) return;
-    trpcClient.agent.recordActivity.mutate({ taskRunId }).catch(() => {});
+    if (!activityRecorded.has(taskRunId)) {
+      activityRecorded.add(taskRunId);
+      trpcClient.agent.recordActivity.mutate({ taskRunId }).catch(() => {});
+    }
     const heartbeat = setInterval(
       () => {
         trpcClient.agent.recordActivity.mutate({ taskRunId }).catch(() => {});
       },
       5 * 60 * 1000,
     );
-    return () => clearInterval(heartbeat);
+    return () => {
+      clearInterval(heartbeat);
+      activityRecorded.delete(taskRunId);
+    };
   }, [session?.taskRunId]);
 
   useEffect(() => {