Django app consumes 100% CPU from infinite loops or full table scans

Django application constantly consumes 100% CPU. Root causes are infinite loops in view code or bad database queries causing full table scans. Long-running queries block workers and consume CPU processing large result sets.

Enable Django Debug Toolbar locally to inspect queries for full table scans. In production, check `SHOW PROCESSLIST` on MySQL or `pg_stat_activity` on PostgreSQL for long-running queries. Review view code for infinite loops. Add query optimization and indexes where needed.