Performance Optimization¶

Techniques and strategies for handling thousands of events efficiently.

Overview¶

CloudEvent Player is optimized to handle large volumes of events without degrading performance. This document covers the performance optimizations implemented and best practices for maintaining smooth operation with thousands of events.

Performance Goals¶

Target Metrics¶

Event Processing:

Receive and parse: < 1ms per event
Storage write: < 5ms per event (async)
Filter evaluation: < 2ms per event
UI update: < 10ms per event

View Rendering:

Initial render: < 200ms for 1000 events
Filter update: < 100ms for 1000 events
View switch: < 150ms
Scroll performance: 60 FPS

Memory Usage:

Per event: ~2KB average
1000 events: ~2MB memory
10000 events: ~20MB memory
Target: < 100MB for typical usage

Optimization Techniques¶

1. Debounced Filtering¶

Problem: Filtering on every keystroke causes excessive re-renders

Solution: Debounce filter calculations by 300ms

// Simplified debounce implementation
let filterTimeout;
function onSearchInput(value) {
  clearTimeout(filterTimeout);
  filterTimeout = setTimeout(() => {
    applyFilters(value);
  }, 300);
}

Benefits:

Reduces filter calculations by ~90%
Smoother typing experience
Lower CPU usage
Better battery life (mobile)

Trade-off: 300ms delay before filters apply

2. Indexed Storage¶

Problem: Searching thousands of events is slow

Solution: IndexedDB indexes on common fields

// Database schema with indexes
objectStore.createIndex("type", "type", { unique: false });
objectStore.createIndex("source", "source", { unique: false });
objectStore.createIndex("time", "time", { unique: false });

Benefits:

O(log n) instead of O(n) queries
Fast filtering by type/source
Efficient time-range queries
Scales to 10,000+ events

Example Performance:

Without index: 100ms to filter 10,000 events
With index: 5ms to filter 10,000 events
Improvement: 20x faster

3. Lazy Loading¶

Problem: Rendering all event data at once is slow

Solution: Render event cards, load details on expand

// Pseudo-code for lazy loading
function renderEvent(event) {
  // Render card immediately (minimal data)
  const card = createEventCard(event.id, event.type);

  // Load full data only when expanded
  card.onExpand = () => {
    loadEventDetails(event.id);
  };
}

Benefits:

Faster initial render
Lower memory usage
Smooth scrolling
Better perceived performance

Trade-off: Slight delay when expanding event

4. Virtual Scrolling (Future)¶

Problem: Rendering 10,000 DOM nodes is slow

Solution: Render only visible events (future enhancement)

Concept:

Viewport (visible area)
  ↓
[Event 50]  ← Rendered
[Event 51]  ← Rendered
[Event 52]  ← Rendered
[Event 53]  ← Rendered
  ↓
(Events 1-49: placeholder)
(Events 54-10000: placeholder)

Expected Benefits:

100+ events in viewport vs 10,000 total
Constant render time regardless of total
Smooth scrolling with any event count
Much lower memory usage

Planned Implementation: Future release

5. Efficient State Updates¶

Problem: Frequent state updates cause excessive re-renders

Solution: Immutable updates with change detection

// Only update if actually changed
function updateState(path, newValue) {
  const oldValue = get(state, path);
  if (oldValue === newValue) return; // Skip if unchanged

  set(state, path, newValue);
  notifySubscribers(path, newValue, oldValue);
}

Benefits:

Avoids unnecessary re-renders
Reduces CPU usage
Smoother UI updates
Better performance overall

6. Batch Operations¶

Problem: Individual operations have overhead

Solution: Batch related operations together

Example - Event Addition:

// Bad - adds one at a time
events.forEach((event) => {
  addEvent(event); // Triggers notification
  saveToIndexedDB(event); // Separate write
});

// Good - batches operations
addEvents(events); // Single notification
saveAllToIndexedDB(events); // Batched write

Benefits:

Fewer DOM updates
Fewer IndexedDB transactions
Lower overhead
Faster bulk operations

7. Throttled UI Updates¶

Problem: UI updates faster than screen refresh rate

Solution: Throttle updates to 60 FPS (16.67ms)

// Simplified throttle for UI updates
let updateScheduled = false;
function scheduleUpdate() {
  if (updateScheduled) return;

  updateScheduled = true;
  requestAnimationFrame(() => {
    updateUI();
    updateScheduled = false;
  });
}

Benefits:

Smooth 60 FPS performance
No wasted rendering
Lower CPU usage
Consistent frame rate

8. Memory Management¶

Problem: Memory leaks and excessive memory usage

Solution: Automatic cleanup and limits

Strategies:

// Limit in-memory events
if (events.length > MAX_EVENTS) {
  events = events.slice(-MAX_EVENTS);
}

// Clean up subscriptions
function cleanup() {
  subscriptions.forEach((unsub) => unsub());
  subscriptions = [];
}

// Clear old events from IndexedDB
if (storageQuotaExceeded()) {
  deleteOldestEvents(1000);
}

Benefits:

Controlled memory usage
No memory leaks
Consistent performance over time
Graceful degradation

Performance Monitoring¶

Browser Developer Tools¶

Performance Tab:

Open DevTools (F12)
Go to Performance tab
Click Record
Perform actions (filter, scroll, etc.)
Stop recording
Analyze flame graph

Look For:

Long tasks (> 50ms)
Layout thrashing
Memory allocations
Frame rate drops

Memory Tab:

Open DevTools
Go to Memory tab
Take heap snapshot
Perform actions
Take another snapshot
Compare snapshots

Look For:

Memory growth
Detached DOM nodes
Large objects
Unexpected allocations

Performance Metrics¶

Key Metrics to Monitor:

Metric	Target	Alert If
Event parse time	< 1ms	> 5ms
Filter time (1000)	< 100ms	> 500ms
Render time (100)	< 100ms	> 500ms
Memory usage (1000)	< 5MB	> 50MB
Frame rate	60 FPS	< 30 FPS
IndexedDB write	< 5ms	> 50ms

Performance Budget¶

Target Budgets:

JavaScript: < 200KB gzipped
CSS: < 50KB gzipped
Memory: < 100MB typical usage
Initial Load: < 2 seconds
Time to Interactive: < 3 seconds

Scalability Limits¶

Tested Limits¶

Event Volume:

✅ 1,000 events: Excellent performance
✅ 10,000 events: Good performance
⚠️ 50,000 events: Acceptable performance (some slowdown)
❌ 100,000+ events: Not recommended (use time filter)

Concurrent Operations:

✅ 1-5 filters: Instant
✅ Continuous SSE stream: No issues
✅ Background tasks: Multiple concurrent
✅ View switching: Smooth

Browser Limits:

IndexedDB: ~50-100MB (browser-dependent)
Memory: Limited by available RAM
DOM nodes: ~10,000 nodes recommended max

Recommendations by Scale¶

Small (< 1,000 events):

No special considerations needed
All features work optimally
Real-time updates smooth
No cleanup needed

Medium (1,000 - 10,000 events):

Use time range filter for focused analysis
Consider periodic storage cleanup
Monitor browser memory usage
All features still work well

Large (10,000 - 50,000 events):

Use time range filter (required)
Regular storage cleanup (admin)
May see slight UI slowdown
Virtual scrolling recommended (future)

Very Large (50,000+ events):

Time range filter essential
Clear storage frequently
Consider server-side filtering
May need to refresh browser periodically

Best Practices¶

For Users¶

Performance Tips:

Use Time Range Filter - Reduce active dataset
Clear Old Events - Ask admin to clean storage periodically
Close Unused Tabs - Free memory for active tab
Specific Filters - Use type/source filters before search
Refresh Browser - If running for extended periods

When to Clear Storage:

Browser feels sluggish
High event count (> 10,000)
Before important testing
After bulk event generation

For Administrators¶

Admin Best Practices:

Monitor Storage - Check event count regularly
Periodic Cleanup - Clear storage weekly/monthly
Communicate - Warn users before clearing
Resource Limits - Set limits on event generation
Observe Patterns - Watch for performance issues

Cleanup Schedule:

Daily - If generating 10,000+ events/day
Weekly - For normal usage
Monthly - For light usage
As Needed - When performance degrades

For Developers¶

Development Best Practices:

Test with Large Datasets - Always test with 10,000+ events
Profile Performance - Use browser dev tools
Monitor Memory - Watch for leaks
Optimize Queries - Use IndexedDB indexes
Debounce/Throttle - Rate-limit expensive operations

Code Review Checklist:

No memory leaks (unsubscribe all subscriptions)
No layout thrashing (batch DOM reads/writes)
Debounced user inputs
Throttled animations
Efficient filters (early exit)
Indexed database queries
Lazy loading where appropriate

Troubleshooting Performance¶

Symptoms and Solutions¶

Slow Filtering:

Symptoms:

Typing in search box is laggy
Filter changes take seconds
UI freezes during filtering

Solutions:

Clear storage (too many events)
Use more specific filters
Close other browser tabs
Check for JavaScript errors

Slow Scrolling:

Symptoms:

Choppy scrolling
Frame rate drops
Browser feels sluggish

Solutions:

Use time range filter
Clear storage
Close unnecessary accordions
Reduce browser zoom level

High Memory Usage:

Symptoms:

Browser tab using > 500MB
System memory pressure
Browser warns about memory

Solutions:

Clear storage immediately
Refresh the page
Close other tabs
Use time range filter

Slow Initial Load:

Symptoms:

Page takes long to load
Events take time to appear
IndexedDB load slow

Solutions:

Clear storage (too many events)
Check browser storage limits
Verify network connection (for SSE)
Clear browser cache

Future Optimizations¶

Planned performance improvements:

1. Virtual Scrolling¶

Render only visible events
Handle 100,000+ events smoothly
Constant memory usage
Implementation planned for v0.4.0

2. Web Workers¶

Move filtering to background thread
Non-blocking UI during heavy operations
Better multi-core utilization
Planned for v0.5.0

3. Compression¶

Compress old events in IndexedDB
Save storage space
Reduce memory usage
Planned for v0.4.0

4. Server-Side Filtering¶

Filter on server before sending
Reduce client-side processing
Lower bandwidth usage
Planned for v0.5.0

5. Incremental Rendering¶

Render events incrementally
Time-sliced rendering
No UI blocking
Planned for v0.4.0

Benchmarks¶

Current Performance (v0.3.0)¶

Event Processing:

Parse 1 event: 0.5ms
Parse 100 events: 45ms
Parse 1000 events: 425ms

Filtering:

Filter 1000 events (indexed): 8ms
Filter 10000 events (indexed): 35ms
Filter 1000 events (search): 25ms

Rendering:

Render 100 events: 95ms
Render 1000 events: 850ms
View switch: 120ms

Memory:

Baseline: 15MB
- 1000 events: 17MB
- 10000 events: 35MB

Next Steps¶

State Management - Understand state optimization
Storage - Learn about storage performance
Filtering - Efficient filtering strategies
Configuration - Configure performance settings