Your VPS feels slow, yet your own processes barely use any CPU. The answer is often CPU steal time: time your virtual CPU wanted to run but the hypervisor gave the physical core to another VM. This guide explains how to measure it and what to do about it.
Before you start
- SSH access to a Linux VPS.
- Background on how vCPUs share cores: CPU pinning and overcommit.
What steal time means
On a KVM VPS, each vCPU is a thread on the host. When the host is busy, your vCPU waits in its run queue. The guest kernel notices that time passed while it was not running and reports it as steal. High steal means the host is contended, not that your server is doing more work.
Measure steal time
In top, the CPU line shows st:
topOver a few seconds with vmstat (the st column):
vmstat 2 10Per CPU with history using the sysstat package:
sar -u 5 12Long-term graphs from tools like Netdata make patterns at certain hours easy to spot.
What values are normal
| Steal | Meaning |
|---|---|
| 0–2% | Normal |
| 2–10% | Some contention; noticeable on latency-sensitive apps |
| Above 10% sustained | Host is overloaded or your plan is heavily oversold |
Short spikes are common; sustained high steal is the problem.
Rule out your own load first
- Check
usandsy(your CPU use) andwa(waiting for disk). Highwais a disk problem, not steal. - Look at load average versus vCPU count.
- Find heavy processes: see top and htop.
What to do about high steal
- Collect evidence: timestamps and
saroutput showing sustained steal. - Contact your provider's support with the data; they can move your VPS to a less busy host.
- Consider a plan with dedicated vCPUs if your workload needs consistent performance.
- Reduce CPU demand with caching so you are less sensitive to contention.
Panel-side tips: fix a slow VPS.
Frequently asked questions
Can I reduce steal time myself?
Not directly; it is caused by the host. You can only reduce your own CPU needs or change plan or host.
Does steal appear on dedicated servers?
No. It only exists in virtual machines.
Why do burstable plans show steal?
Some plans throttle you after using your CPU credits, which can show as steal.