How to Detect and Troubleshoot CPU Core Failures

Detecting and troubleshooting CPU core failures in HPC systems is crucial to maintaining reliability and performance. Here's a practical approach:

Step 1: Identify Symptoms

• Sudden performance degradation, system instability, or unexpected node reboots.
• Errors in job logs related to CPU or core operations.

Step 2: Check System Logs

• Inspect system logs for core-related errors:
• dmesg | grep -i 'cpu.*error'
• Check scheduler logs for job failures indicating CPU issues.

Step 3: Use Diagnostic Tools

• Run diagnostics using tools like stress-ng, mprime, or vendor-specific diagnostics:
• stress-ng --cpu <num_cores> --timeout 30m

Step 4: Monitor Core Usage and Health

• Check real-time CPU core utilization and identify anomalies:
• htop
• Verify CPU core status using:
• lscpu

Step 5: BIOS and Firmware Checks

• Ensure BIOS and firmware are up to date.
• Review BIOS logs for hardware-level core failure messages.

Step 6: Physical Inspection

• Inspect physical hardware for overheating or damage.
• Ensure proper seating of CPU and adequate cooling solutions.

Step 7: Mitigate or Disable Faulty Cores

• Temporarily disable faulty cores via OS or BIOS if replacement isn't immediately possible.

Step 8: CPU Replacement

• Replace CPU if a core failure is confirmed and cannot be resolved.

Step 9: Document and Monitor

• Keep detailed records of core failure incidents, diagnostics, resolutions, and follow-up actions.
• Continuously monitor CPU performance post-resolution.

Following these steps systematically ensures effective identification, troubleshooting, and resolution of CPU core failures, maintaining the stability and performance of your HPC environment.