Advertisement
Interview Question
What do the 1, 5, and 15 minute load averages indicate on Linux, and how do you interpret them relative to CPU cores?
Key Points to Cover
- Load average = runnable + uninterruptible tasks
- Compare load to number of CPU cores (e.g., load 8 on 8 cores ≈ full utilization)
- Trends (1/5/15) show short vs long-term pressure
Evaluation Rubric
Defines load average correctly34% weight
Relates load to core count33% weight
Explains 1/5/15 significance33% weight
Hints
- 💡Uninterruptible often indicates I/O wait.
Common Pitfalls to Avoid
- ⚠️Confusing load average solely with CPU utilization, neglecting the 'uninterruptible' task component (e.g., I/O wait).
- ⚠️Failing to consider the number of CPU cores when interpreting the load average, leading to misdiagnosis of system health.
- ⚠️Ignoring the trend across the 1, 5, and 15 minute values, thus missing whether the load is spiking, decreasing, or sustained.
- ⚠️Misinterpreting a high load average as always 'bad' without understanding the nature of the workload (e.g., intentional heavy batch processing).
- ⚠️Not understanding that high load average can be caused by I/O bottlenecks, not just CPU contention.
Potential Follow-up Questions
- ❓How to identify I/O bottlenecks?
- ❓Which tools help (iostat, pidstat)?
Advertisement
Related Questions
Questions that share similar topics with this one
Node CPU Thrashing
Intermediate🔧 Troubleshooting Scenarios•10 min•Scenario
Find Top CPU Processes in Linux
Beginner📞 Phone Screen•1 min•Phone
Troubleshooting High Memory in Linux
Intermediate📞 Phone Screen•2 min•Phone
Find Large Files with Bash
Beginner📞 Phone Screen•1 min•Phone
Investigating High CPU Usage in Kubernetes Pods
Advanced🔬 Technical Deep Dive•5 min•Technical