Task: Dashboard Performance Testing and Optimization

[prosdev]

Branch: chore/dashboard-perf
Priority: High
Parent Epic: #145
Type: Task

Description

Conduct thorough performance testing of the dashboard system to ensure it meets performance targets. Profile stats aggregation overhead, API response times, and frontend rendering. Optimize any bottlenecks found.

Acceptance Criteria

• Stats aggregation adds <5% overhead to indexing
• API endpoints respond in <100ms for typical repos
• Dashboard loads in <2s on 10k file repository
• Charts render smoothly (60fps)
• Memory usage is reasonable (<500MB for large repos)
• Performance benchmarks documented
• Optimization recommendations for large repos

Technical Requirements

Benchmarks to Run:

1. Indexing Performance

   • Measure indexing time before/after stats aggregation
   • Test with various repo sizes (100, 1k, 10k, 50k files)
   • Measure memory usage
   • Profile hotspots with Node.js profiler

2. API Performance

   • Measure /api/stats response time
   • Test with various repo sizes
   • Test concurrent requests
   • Measure memory usage per request

3. Frontend Performance

   • Lighthouse scores (Performance, Accessibility)
   • Time to first paint
   • Time to interactive
   • Chart rendering performance
   • Bundle size analysis

Optimization Strategies:

1. Stats Aggregation

   • Use efficient data structures (Map vs Object)
   • Incremental aggregation (no post-processing)
   • Limit memory usage (streaming where possible)
   • Cache computed values

2. API Layer

   • Implement response caching
   • Add ETag support
   • Compress responses (gzip)
   • Lazy load large datasets

3. Frontend

   • Code splitting for charts
   • Lazy load Tremor components
   • Memoize expensive calculations
   • Virtualize long lists
   • Optimize bundle size

Performance Targets:

• Indexing overhead: <5%
• API response: <100ms (p95)
• Dashboard load: <2s
• Charts render: <500ms
• Memory usage: <500MB for 10k files

Testing:

# Indexing performance
hyperfine 'dev index /path/to/large/repo' --warmup 1

# API performance
wrk -t2 -c10 -d30s http://localhost:3000/api/stats

# Frontend performance
lighthouse http://localhost:3000 --view

Documentation:

• Create apps/dashboard/PERFORMANCE.md
• Document benchmarks
• Document optimization techniques
• Provide guidance for large repositories

Files to Create:

• apps/dashboard/PERFORMANCE.md
• benchmarks/dashboard-perf.sh
• benchmarks/results.md

Files to Modify:

• Optimize based on profiling results
• Add performance comments to critical paths