Silent Data Corruption
Silent data corruption during training causes wrong results without error messages, often from hardware issues.
Silent data corruption during training causes wrong results without error messages, often from hardware issues.
What this failure is
Silent Data Corruption is a Reliability failure seen during ML training runs. Silent data corruption during training causes wrong results without error messages, often from hardware issues. Common tags: Silent Corruption, Bit Flip, Ecc, Reliability.
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Why it happens (the mechanism)
GPU memory bit flips (cosmic rays, hardware issues). Storage bit flips in checkpoint. CPU memory errors. Network bit flips in distributed training. Taken together, these mechanisms explain why the failure is reproducible, why it tends to surface on specific workloads or scales, and why generic mitigation attempts often fall short without addressing the underlying cause.
What you'll observe
- Training loss is wrong but no error
- Model accuracy is poor without obvious cause
- Results are non-reproducible across runs
Common symptoms and what they mean
| Symptom | Why it happens |
|---|---|
| Same code gives different results | GPU memory bit flips (cosmic rays, hardware issues) |
| Bit flips in memory or storage | Storage bit flips in checkpoint |
| Some samples produce different outputs | CPU memory errors |
Which systems are affected
- Long-running training
- Large-scale GPU training
- High-performance computing
How to confirm this is the problem
Use this checklist to test the hypothesis against a small reproduction. No single line proves the root cause, so preserve the preceding events and compare one variable at a time.
- ✓Reproduce the failure from a clean checkpoint/seed: the symptom must appear without warm-up state from a previous run.
- ✓Verified signal present: Same code gives different results
- ✓Verified signal present: Bit flips in memory or storage
- ✓Verified signal present: Some samples produce different outputs
- ✓A targeted fix from the "How to fix it" section eliminates or substantially reduces the symptom within one validation pass.
The fix and the prevention pattern
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Diagnose this failure in VS Code
Select the traceback or open the failed terminal, then run Denpex locally to see the initiating rank, collateral failures, exact fix, and verification command without uploading the log.
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Root cause
- GPU memory bit flips (cosmic rays, hardware issues)
- Storage bit flips in checkpoint
- CPU memory errors
- Network bit flips in distributed training
The fix and how to prevent it
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