CRE-2025-0177
Redis Slow Query Performance DegradationCriticalImpact: 6/10Mitigation: 8/10
Description
Detects slow query execution in Redis that exceeds configured thresholds. Slow queries indicate performance problems that can impact overall Redis responsiveness and application latency.\n
Mitigation
IMMEDIATE ACTIONS:\n- Check slowlog: `redis-cli SLOWLOG GET 10`\n- Monitor current operations: `redis-cli --latency`\n- Identify blocking clients: `redis-cli CLIENT LIST`\n- Check CPU usage: `redis-cli INFO cpu`\n\nOPTIMIZATION:\n- Replace KEYS with SCAN:\n ```\n # Bad: KEYS pattern*\n # Good: SCAN 0 MATCH pattern* COUNT 100\n ```\n- Use pagination for large collections:\n ```\n ZRANGE key start stop\n LRANGE key start stop\n ```\n- Optimize Lua scripts:\n - Minimize Redis calls within scripts\n - Avoid complex computations\n- Break large operations into smaller batches\n\nCONFIGURATION:\n- Adjust slowlog threshold:\n `redis-cli CONFIG SET slowlog-log-slower-than 10000`\n- Increase slowlog size:\n `redis-cli CONFIG SET slowlog-max-len 128`\n- Enable latency monitoring:\n `redis-cli CONFIG SET latency-monitor-threshold 100`\n\nPREVENTION:\n- Regular slowlog analysis\n- Use appropriate data structures\n- Implement query timeouts in clients\n- Cache computation results\n- Use Redis modules for complex operations\n- Monitor and alert on slow query patterns\n