Why Your Bulk Deletes Fail at Scale: PostgreSQL's MVCC and WAL Wake Effect

Bulk row deletion in PostgreSQL extends far beyond the SQL statement itself—the real performance bottleneck lies in managing MVCC tuple versioning, WAL write amplification, and replication slot consumption. This deep dive reveals why improper deletion strategies can trigger disk space exhaustion and replication lag in production systems, making it essential for database operators to understand the subsystems that govern cleanup operations.