- Created tests/performance/test_nfo_batch_performance.py with 11 comprehensive tests
- Test classes: Concurrent NFO creation, TMDB API batching optimization, media download concurrency, memory usage, scalability
- Coverage: 10/50/100 series concurrent creation, TMDB API call optimization, rate limit handling, media downloads, memory efficiency, linear scalability
- Performance targets: 10 series < 5s, 50 series < 20s, 100 series < 30s - all met
- 11/11 tests passing - excellent performance coverage for batch operations
- Validates concurrent operations, API optimization, memory usage < 100MB for 100 series