Node process 100 CPU fix
A Node process at 100% CPU usually means your event loop is spending too much time on computation or pathological code paths.
Common symptoms
- One Node PID pegs a core
- Latency spikes while throughput stalls
- Restart temporarily clears the issue
Likely causes
- Infinite loops or busy waiting
- Large synchronous transforms
- Compression, crypto, or parsing under load
Evidence to look for
Same process remains at top CPU across snapshots
Flame graph shows concentrated hot functions
Request latency worsens in parallel with CPU
What it usually means
Node is most vulnerable when synchronous work overwhelms the event loop. The right fix is usually structural, not just horizontal scaling.
What to do next
- 1Break synchronous work out of request handling
- 2Use worker threads or background jobs
- 3Profile and optimize the hottest function first
See what's causing your CPU
cpum.ai turns CPU, process, disk, and memory signals into plain-English explanations with evidence.
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