Emit a warning when memory usage exceeds 7GB (#7613)

packages/cli/src/ui/AppContainer.tsx

@@ -47,6 +47,7 @@ import { validateAuthMethod } from '../config/auth.js';
 import { loadHierarchicalGeminiMemory } from '../config/config.js';
 import process from 'node:process';
 import { useHistory } from './hooks/useHistoryManager.js';
+import { useMemoryMonitor } from './hooks/useMemoryMonitor.js';
 import { useThemeCommand } from './hooks/useThemeCommand.js';
 import { useAuthCommand } from './auth/useAuth.js';
 import { useQuotaAndFallback } from './hooks/useQuotaAndFallback.js';
@@ -123,6 +124,7 @@ const SHELL_HEIGHT_PADDING = 10;
 export const AppContainer = (props: AppContainerProps) => {
   const { settings, config, initializationResult } = props;
   const historyManager = useHistory();
+  useMemoryMonitor(historyManager);
   const [corgiMode, setCorgiMode] = useState(false);
   const [debugMessage, setDebugMessage] = useState<string>('');
   const [quittingMessages, setQuittingMessages] = useState<

packages/cli/src/ui/components/HistoryItemDisplay.tsx

@@ -14,6 +14,7 @@ import { ErrorMessage } from './messages/ErrorMessage.js';
 import { ToolGroupMessage } from './messages/ToolGroupMessage.js';
 import { GeminiMessageContent } from './messages/GeminiMessageContent.js';
 import { CompressionMessage } from './messages/CompressionMessage.js';
+import { WarningMessage } from './messages/WarningMessage.js';
 import { Box } from 'ink';
 import { AboutBox } from './AboutBox.js';
 import { StatsDisplay } from './StatsDisplay.js';
@@ -66,6 +67,7 @@ export const HistoryItemDisplay: React.FC<HistoryItemDisplayProps> = ({
       />
     )}
     {item.type === 'info' && <InfoMessage text={item.text} />}
+    {item.type === 'warning' && <WarningMessage text={item.text} />}
     {item.type === 'error' && <ErrorMessage text={item.text} />}
     {item.type === 'about' && (
       <AboutBox

packages/cli/src/ui/components/messages/WarningMessage.tsx

@@ -0,0 +1,32 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import type React from 'react';
+import { Box, Text } from 'ink';
+import { Colors } from '../../colors.js';
+import { RenderInline } from '../../utils/InlineMarkdownRenderer.js';
+
+interface WarningMessageProps {
+  text: string;
+}
+
+export const WarningMessage: React.FC<WarningMessageProps> = ({ text }) => {
+  const prefix = '⚠ ';
+  const prefixWidth = 3;
+
+  return (
+    <Box flexDirection="row" marginTop={1}>
+      <Box width={prefixWidth}>
+        <Text color={Colors.AccentYellow}>{prefix}</Text>
+      </Box>
+      <Box flexGrow={1}>
+        <Text wrap="wrap" color={Colors.AccentYellow}>
+          <RenderInline text={text} />
+        </Text>
+      </Box>
+    </Box>
+  );
+};

packages/cli/src/ui/hooks/useMemoryMonitor.test.ts

@@ -0,0 +1,71 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { renderHook } from '@testing-library/react';
+import { vi } from 'vitest';
+import {
+  useMemoryMonitor,
+  MEMORY_CHECK_INTERVAL,
+  MEMORY_WARNING_THRESHOLD,
+} from './useMemoryMonitor.js';
+import process from 'node:process';
+import { MessageType } from '../types.js';
+
+describe('useMemoryMonitor', () => {
+  const memoryUsageSpy = vi.spyOn(process, 'memoryUsage');
+  const addItem = vi.fn();
+
+  beforeEach(() => {
+    vi.useFakeTimers();
+    vi.clearAllMocks();
+  });
+
+  afterEach(() => {
+    vi.useRealTimers();
+  });
+
+  it('should not warn when memory usage is below threshold', () => {
+    memoryUsageSpy.mockReturnValue({
+      rss: MEMORY_WARNING_THRESHOLD / 2,
+    } as NodeJS.MemoryUsage);
+    renderHook(() => useMemoryMonitor({ addItem }));
+    vi.advanceTimersByTime(10000);
+    expect(addItem).not.toHaveBeenCalled();
+  });
+
+  it('should warn when memory usage is above threshold', () => {
+    memoryUsageSpy.mockReturnValue({
+      rss: MEMORY_WARNING_THRESHOLD * 1.5,
+    } as NodeJS.MemoryUsage);
+    renderHook(() => useMemoryMonitor({ addItem }));
+    vi.advanceTimersByTime(MEMORY_CHECK_INTERVAL);
+    expect(addItem).toHaveBeenCalledTimes(1);
+    expect(addItem).toHaveBeenCalledWith(
+      {
+        type: MessageType.WARNING,
+        text: 'High memory usage detected: 10.50 GB. If you experience a crash, please file a bug report by running `/bug`',
+      },
+      expect.any(Number),
+    );
+  });
+
+  it('should only warn once', () => {
+    memoryUsageSpy.mockReturnValue({
+      rss: MEMORY_WARNING_THRESHOLD * 1.5,
+    } as NodeJS.MemoryUsage);
+    const { rerender } = renderHook(() => useMemoryMonitor({ addItem }));
+    vi.advanceTimersByTime(MEMORY_CHECK_INTERVAL);
+    expect(addItem).toHaveBeenCalledTimes(1);
+
+    // Rerender and advance timers, should not warn again
+    memoryUsageSpy.mockReturnValue({
+      rss: MEMORY_WARNING_THRESHOLD * 1.5,
+    } as NodeJS.MemoryUsage);
+    rerender();
+    vi.advanceTimersByTime(MEMORY_CHECK_INTERVAL);
+    expect(addItem).toHaveBeenCalledTimes(1);
+  });
+});

packages/cli/src/ui/hooks/useMemoryMonitor.ts

@@ -0,0 +1,41 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { useEffect } from 'react';
+import process from 'node:process';
+import { type HistoryItemWithoutId, MessageType } from '../types.js';
+
+export const MEMORY_WARNING_THRESHOLD = 7 * 1024 * 1024 * 1024; // 7GB in bytes
+export const MEMORY_CHECK_INTERVAL = 60 * 1000; // one minute
+
+interface MemoryMonitorOptions {
+  addItem: (item: HistoryItemWithoutId, timestamp: number) => void;
+}
+
+export const useMemoryMonitor = ({ addItem }: MemoryMonitorOptions) => {
+  useEffect(() => {
+    const intervalId = setInterval(() => {
+      const usage = process.memoryUsage().rss;
+      if (usage > MEMORY_WARNING_THRESHOLD) {
+        addItem(
+          {
+            type: MessageType.WARNING,
+            text:
+              `High memory usage detected: ${(
+                usage /
+                (1024 * 1024 * 1024)
+              ).toFixed(2)} GB. ` +
+              'If you experience a crash, please file a bug report by running `/bug`',
+          },
+          Date.now(),
+        );
+        clearInterval(intervalId);
+      }
+    }, MEMORY_CHECK_INTERVAL);
+
+    return () => clearInterval(intervalId);
+  }, [addItem]);
+};

packages/cli/src/ui/types.ts

@@ -106,6 +106,11 @@ export type HistoryItemError = HistoryItemBase & {
   text: string;
 };
 
+export type HistoryItemWarning = HistoryItemBase & {
+  type: 'warning';
+  text: string;
+};
+
 export type HistoryItemAbout = HistoryItemBase & {
   type: 'about';
   cliVersion: string;
@@ -170,6 +175,7 @@ export type HistoryItemWithoutId =
   | HistoryItemGeminiContent
   | HistoryItemInfo
   | HistoryItemError
+  | HistoryItemWarning
   | HistoryItemAbout
   | HistoryItemHelp
   | HistoryItemToolGroup
@@ -186,6 +192,7 @@ export type HistoryItem = HistoryItemWithoutId & { id: number };
 export enum MessageType {
   INFO = 'info',
   ERROR = 'error',
+  WARNING = 'warning',
   USER = 'user',
   ABOUT = 'about',
   HELP = 'help',

packages/cli/tsconfig.json

@@ -66,6 +66,7 @@
     "src/ui/components/shared/vim-buffer-actions.test.ts",
     "src/ui/components/StatsDisplay.test.tsx",
     "src/ui/components/ToolStatsDisplay.test.tsx",
+    "src/ui/components/WarningMessage.test.tsx",
     "src/ui/contexts/SessionContext.test.tsx",
     "src/ui/hooks/slashCommandProcessor.test.ts",
     "src/ui/hooks/useAtCompletion.test.ts",