Disk bottleneck CPU symptoms
A disk bottleneck often masquerades as a CPU problem. The symptoms overlap, but the evidence tells a different story.
Evidence to look for
iowait is elevated
Disk utilization near 100%
CPU and disk metrics rise together
Await times exceed 20ms
What it usually means
The CPU chart spikes because threads are waiting on disk and creating scheduling pressure. The real bottleneck is storage, not compute.
What to do next
- 1Check disk utilization and await times first
- 2Move to faster storage if disk is saturated
- 3Reduce IO concurrency or add caching
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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