diff --git a/.planning/phases/19-audit-and-discovery/19-AUDIT.md b/.planning/phases/19-audit-and-discovery/19-AUDIT.md index 4299f1142..38a3c29c0 100644 --- a/.planning/phases/19-audit-and-discovery/19-AUDIT.md +++ b/.planning/phases/19-audit-and-discovery/19-AUDIT.md @@ -230,3 +230,257 @@ The `callbacks` object is defined within the useEffect, so the cleanup function --- +## Session Screen Audit + +**Files Audited:** +- `jam-ui/src/components/client/JKSessionScreen.js` +- `jam-ui/src/hooks/useJamServer.js` +- `jam-ui/src/hooks/useSessionStats.js` +- `jam-ui/src/hooks/useSessionModel.js` +- `jam-ui/src/components/client/JKSessionBackingTrackPlayer.js` +- `jam-ui/src/components/client/JKSessionJamTrackPlayer.js` + +**Requirements Coverage:** SESS-01, SESS-02, SESS-03 + +### JKSessionScreen.js + +**useEffect Hook Count:** 14 total hooks + +| Line | Pattern | Description | Has Cleanup | Severity | Notes | +|------|---------|-------------|-------------|----------|-------| +| 454-472 | setTimeout x3 | Track sync timers (timer1, timer2, timer3) | YES | LOW | Properly cleared at lines 470-472 | +| 616-629 | Callback registration | WebSocket message callbacks stored in state | YES | LOW | Unregistered via unregisterMessageCallbacks on leave | +| 985 | setTimeout | Video loading button timeout | NO | LOW | Short one-time delay in finally block, not a leak | +| 1032-1040 | useEffect | Session state sync | YES | LOW | Cleanup return function present | +| 1180-1195 | window.JK.HandleAlertCallback | Global alert callback registration | YES | LOW | Deleted on cleanup | + +**Analysis:** JKSessionScreen.js is a large component (1740 lines) with 14 useEffect hooks. The majority have proper cleanup functions. The track sync timers at lines 454-472 are well-managed with refs and cleanup. The WebSocket callback registration pattern stores callbacks in state and unregisters them on leave. + +**SESS-01 - POTENTIAL ISSUE:** The callback registration pattern (lines 616-629) stores callbacks in React state. If the leave handler doesn't execute (e.g., browser crash, navigation away), callbacks may remain registered. However, this is mitigated by the jamServer cleanup on connection close. + +### useJamServer.js + +| Line | Pattern | Description | Has Cleanup | Severity | Notes | +|------|---------|-------------|-------------|----------|-------| +| 270-272 | setTimeout | `reconnectTimeoutRef` for reconnection delay | YES | LOW | Cleared in disconnect() and on unmount | +| 311-320 | setTimeout | Request timeout in sendRequest | YES | LOW | Cleared via clearTimeout | +| 485-493 | setInterval x3 | `heartbeatInterval`, `heartbeatAckCheckInterval`, `startHeartbeatTimeout` | YES | LOW | All cleared via stopHeartbeat() | +| 608-634 | setTimeout | `activityTimeout` for user activity tracking | YES | LOW | Cleared in markActive() and cleanup | + +**Analysis:** useJamServer.js has comprehensive cleanup for all timers: +- `stopHeartbeat()` (lines 485-493) clears all three heartbeat-related timers +- `disconnect()` clears reconnect timeout +- Activity timeout is cleared when marking active and on cleanup + +All timer patterns follow best practices with refs and explicit cleanup. + +### useSessionStats.js + +| Line | Pattern | Description | Has Cleanup | Severity | Notes | +|------|---------|-------------|-------------|----------|-------| +| 151-153 | setInterval | Stats refresh every 2000ms | YES | LOW | Cleared via return () => clearInterval(intervalId) | + +**Analysis:** Clean implementation. The stats polling interval is stored in a local variable and cleared in the useEffect return function. + +```javascript +// Lines 151-153 +const intervalId = setInterval(() => { + fetchStats(); +}, 2000); + +return () => clearInterval(intervalId); +``` + +### useSessionModel.js + +| Line | Pattern | Description | Has Cleanup | Severity | Notes | +|------|---------|-------------|-------------|----------|-------| +| 93 | useRef | `backendMixerAlertThrottleTimerRef` for throttling | YES | LOW | Cleared at lines 171-178 | +| 171-178 | useEffect | Cleanup effect for throttle timer | YES | LOW | Properly clears timeout on unmount | + +**Analysis:** The throttle timer for backend mixer alerts is properly managed: + +```javascript +// Lines 171-178 +useEffect(() => { + return () => { + if (backendMixerAlertThrottleTimerRef.current) { + clearTimeout(backendMixerAlertThrottleTimerRef.current); + } + }; +}, []); +``` + +### JKSessionBackingTrackPlayer.js + +| Line | Pattern | Description | Has Cleanup | Severity | Notes | +|------|---------|-------------|-------------|----------|-------| +| 155-218 | setInterval | Position/duration polling | YES | LOW | Cleared at lines 222-226 | +| 230-239 | useEffect | Unmount cleanup for playback | YES | LOW | Stops playback on unmount | +| 301 | setTimeout | Async Promise delay | N/A | LOW | One-time delay in async function | + +**Analysis:** The position polling interval is properly cleaned up: + +```javascript +// Lines 222-226 +return () => { + if (intervalId) { + clearInterval(intervalId); + } +}; +``` + +The polling interval also adjusts based on visibility state (500ms when visible, 2000ms when hidden), reducing CPU usage when tab is backgrounded. + +### JKSessionJamTrackPlayer.js + +| Line | Pattern | Description | Has Cleanup | Severity | Notes | +|------|---------|-------------|-------------|----------|-------| +| 415-461 | setInterval | Position/duration polling | YES | LOW | Cleared via return clearInterval(intervalId) | +| 465-473 | addEventListener | visibilitychange listener | YES | LOW | Removed on cleanup | + +**Analysis:** Both the polling interval and visibility listener are properly cleaned up. The pattern matches JKSessionBackingTrackPlayer.js with visibility-aware polling rates. + +### Session Screen Findings Summary + +| ID | Finding | File | Lines | Severity | Fix Recommendation | +|----|---------|------|-------|----------|-------------------| +| SESS-01 | Callback unregistration relies on leave handler | JKSessionScreen.js | 616-629 | LOW | Add backup cleanup in useEffect return | +| SESS-02 | No issues found | useJamServer.js | N/A | N/A | All timers properly cleaned up | +| SESS-03 | No issues found | useSessionStats.js, useSessionModel.js | N/A | N/A | All timers properly cleaned up | + +**Overall Assessment:** The session screen and supporting hooks have well-implemented cleanup patterns. No critical memory leaks were identified in this area. The primary leak sources are in the VU meter (vuStates accumulation) and chat (unbounded message growth) systems. + +--- + +## Priority Summary + +### HIGH Severity Findings (Likely Causes of 10-Minute Freeze) + +These findings represent unbounded state growth that accumulates over time and are the most likely causes of the session freeze: + +| Priority | ID | Finding | Impact | Estimated Fix Effort | +|----------|----|---------|---------|--------------------| +| 1 | VUMTR-02 | vuStates object grows unbounded | State object grows with each track change, never pruned | Low - Add removeVuState function | +| 2 | VUMTR-03 | No per-mixer cleanup on track leave | Stale entries accumulate throughout session | Low - Call removeVuState on track leave | +| 3 | CHAT-01 | Messages accumulate without limit | Memory grows linearly with chat activity | Medium - Add MAX_MESSAGES constant and slice() | + +### MEDIUM Severity Findings (May Contribute to Degradation) + +These findings affect performance but are less likely to cause the freeze: + +| Priority | ID | Finding | Impact | Estimated Fix Effort | +|----------|----|---------|---------|--------------------| +| 4 | VUMTR-01 | VU callback throttling disabled | High-frequency callbacks may cause render thrashing | Low - Re-enable throttling | +| 5 | CHAT-03 | No message cleanup on session leave | Memory not released when leaving session | Low - Add clearAllMessages action | + +### LOW Severity Findings (Minor or Properly Handled) + +These findings are included for completeness but do not require immediate action: + +| Priority | ID | Finding | Impact | Estimated Fix Effort | +|----------|----|---------|---------|--------------------| +| 6 | CHAT-02 | chatState in useEffect dependencies | Performance, not memory | Low - Extract needed values | +| 7 | SESS-01 | Callback unregistration relies on leave handler | Edge case only | Low - Add backup cleanup | + +--- + +## Implementation Recommendations + +### Phase 20: VU Meter Fixes + +**Objective:** Fix unbounded vuStates growth pattern + +**Tasks:** +1. **Add removeVuState function to useVuHelpers.js** + - Add `removeVuState(mixerId)` callback that deletes specific mixer entries + - Export from VuContext for consumers + +2. **Integrate cleanup with track lifecycle** + - Call `removeVuState(mixerId)` when a track leaves the session + - Hook into existing track leave detection in useMixerHelper.js + +3. **Re-enable VU callback throttling (optional)** + - Uncomment or re-implement throttling in useMixerStore.js lines 141-152 + - Set reasonable throttle interval (e.g., 50-100ms) + +**Files to modify:** +- `jam-ui/src/hooks/useVuHelpers.js` +- `jam-ui/src/context/VuContext.js` +- `jam-ui/src/hooks/useMixerHelper.js` or `jam-ui/src/hooks/useMixerStore.js` + +**Verification:** +- Join session, add/remove tracks multiple times +- Monitor vuStates object size - should stay bounded +- Memory should not grow after tracks removed + +### Phase 21: Chat Window Fixes + +**Objective:** Implement message limit and cleanup + +**Tasks:** +1. **Add MAX_MESSAGES constant to sessionChatSlice.js** + - Define `const MAX_MESSAGES = 500` (or appropriate limit) + - Apply limit in `receiveMessage` reducer with `slice(-MAX_MESSAGES)` + - Apply limit in `fetchMessagesSuccess` reducer + +2. **Add clearAllMessages action** + - Create `clearAllMessages` reducer that resets `messagesByChannel` to `{}` + - Dispatch on session leave from JKSessionScreen.js + +3. **Optimize chatState dependencies (optional)** + - Extract only needed values from chatState selector in useSessionWebSocket.js + - Reduce unnecessary effect re-runs + +**Files to modify:** +- `jam-ui/src/store/features/sessionChatSlice.js` +- `jam-ui/src/components/client/JKSessionScreen.js` (for cleanup dispatch) + +**Verification:** +- Send 600+ messages in a session +- Verify only latest 500 are retained +- Memory should plateau after limit reached + +### Phase 22: Session Screen Hardening + +**Objective:** Add defensive cleanup patterns + +**Tasks:** +1. **Add backup callback cleanup in JKSessionScreen.js** + - Add useEffect return function that unregisters callbacks + - Ensures cleanup even if leave handler doesn't execute + +2. **Verify all exit paths trigger cleanup** + - Trace error, timeout, and navigation exit paths + - Ensure cleanup runs in all cases + +3. **Add memory monitoring for regression prevention** + - Document manual testing procedure + - Consider adding performance markers for automated detection + +**Files to modify:** +- `jam-ui/src/components/client/JKSessionScreen.js` + +**Verification:** +- Test various exit scenarios (leave, error, timeout, navigation) +- Confirm cleanup runs in all cases +- Session stable after 15+ minutes + +--- + +## Conclusion + +The audit identified **3 HIGH severity** findings that are the most likely causes of the ~10-minute session freeze: + +1. **VUMTR-02 & VUMTR-03:** VU meter state accumulates without cleanup - affects every session with track changes +2. **CHAT-01:** Chat messages grow unbounded - affects sessions with active chat + +The session screen base components (JKSessionScreen.js, useJamServer.js, player components) have **well-implemented cleanup patterns** and are not primary contributors to the leak. + +**Recommended fix order:** +1. Phase 20: VU meter fixes (highest impact, lowest effort) +2. Phase 21: Chat fixes (high impact, medium effort) +3. Phase 22: Session hardening (defensive, low priority) + +Total estimated effort: 2-3 hours for Phases 20-21, 1 hour for Phase 22. +