- Reduce cache size from 8GB to 512MB (still plenty for 2.4GB DB)
- Reduce mmap_size from 10GB to 256MB (reasonable default)
- Use default page size (4KB) instead of 8KB
- Use default WAL checkpoint interval (1000 pages)
- Remove redundant pragmas (threads, cache_spill, read_uncommitted)
- Clean up connection string to only use _txlock parameter
- Keep synchronous=OFF for performance (since we have mutex protection)
- Add internal mutex to Database struct with lock/unlock wrappers
- Add debug logging for lock acquisition and release with timing
- Wrap all write operations with database mutex
- Use _txlock=immediate in SQLite connection string
This works around apparent issues with SQLite's internal locking
not properly respecting busy_timeout in production environment.
- Add _txlock=immediate to SQLite connection string
- This prevents deadlocks by acquiring write locks at transaction start
- Multiple concurrent writers now queue properly instead of failing instantly
- Resolves 'database table is locked' errors in production
