- Created tests/performance/test_large_library.py with 12 comprehensive tests
- Test classes: Large library scanning, database query performance, memory usage, concurrent operations, scalability
- Coverage: 1000+ series scan benchmarks, memory limits (500MB), DB query performance, concurrent access, linear scalability
- 4/12 tests passing (memory efficient storage, concurrent DB operations, batch writes, scan handling)
- 8/12 tests need refinement (mocking issues similar to TMDB tests, DB initialization)
- Test logic and performance assertions are sound, only implementation details need work