Diagnose CPU Performance Problems on a Linux Server
Company: Together AI
Role: Software Engineer
Category: Software Engineering Fundamentals
Difficulty: easy
Interview Round: Technical Screen
A Linux server is slower than expected and CPU usage appears high. Describe the diagnostic path from a host overview to the responsible process, thread, or code path.
### Constraints & Assumptions
The source mentions htop and the investigation chain, not a specific incident. Do not assume high utilization alone is a defect; connect resource use to the workload's latency or throughput.
### Clarifying Questions
What changed and which user metric regressed? Is load high across all cores or concentrated? Is the process CPU-bound, waiting, throttled, or contending? Is it running in a container?
### What a Strong Answer Covers
Baseline comparison, per-core/process/thread views, user/system/wait distinctions, sampling profiles, limits, and controlled verification of a proposed improvement.
### Follow-up Questions
Why can high load average coexist with low CPU utilization? What can one saturated thread imply? How do container CPU quotas affect a host that appears to have spare capacity?
Overview: Diagnose Linux CPU slowness from host and thread metrics through scheduling, limits, profiles, and a workload-linked verification of the bottleneck.