Analyzing the Slow Log
Use the Redis slow log to find commands that block the server, interpret entries, and tune the thresholds that capture them.
Redis Is Single-Threaded
Command execution in Redis is effectively single-threaded. One slow command blocks every other client. The slow log records commands whose execution time exceeds a threshold, so you can hunt down these blockers.
What It Measures
The slow log times only command execution, not network or I/O wait. So a logged entry means Redis itself spent that long, usually on an expensive operation over many elements.
All lessons in this course
- Redis Monitoring Tools
- Diagnosing Performance Issues
- Performance Tuning & Optimization
- Analyzing the Slow Log