High steal values on your vServer almost always come from a configuration that was not fully applied after an upgrade. Check the value with top or vmstat. If it stays high, open a ticket: we check the configuration and then ask you for a regular ?Stop und Start? (stop and start) so the new values take effect.

What is steal?

Your vServer runs as a virtual machine on a host. Steal (abbreviated st) is the share of time in which your server wanted to compute, but the host did not give it any CPU time. Linux inside the VM only sees that the cores are waiting and reports it as steal. A few percent during load peaks are normal. Permanently double-digit values are unusual and your server will feel noticeably slow.

How to check the steal value

Connect via SSH and start top. In the line ?%Cpu(s)? the value behind st is your steal. Alternatively, vmstat shows it in the last column st:

top
vmstat 1 10

Watch the value for a few minutes and note the times when it is high. That helps us with the analysis. On Windows, Task Manager does not show a steal value. There you recognize the problem by high CPU usage while the process tab shows little load.

Most common cause: CPU limit does not match the core count

In the vast majority of cases it is a configuration issue after an upgrade. If you added cores, in rare cases the CPU percentage value is not raised with them. Your server then reports, for example, 6 cores but may only use 200 % CPU time. For Linux this looks like steal, usually between 50 and 70 %, although the host is not busy at all.

This short test shows the pattern. It loads all cores fully, so stop it again right afterwards:

for i in $(seq "$(nproc)"); do yes > /dev/null & done
top
# stop it afterwards:
pkill yes

With 6 cores and a limit of 200 %, the summary line of top shows about a third at us and the rest at st. In that case the limit is very likely the cause.

What to do in this case

  1. Open a support ticket and tell us you see high steal values (details below). Normal priority is enough, this is not an emergency.
  2. We check your server’s configuration and correct the CPU value.
  3. Afterwards we ask you to do a regular ?Stop und Start? (stop and start) in Vionity so the new values are applied. A reboot inside the operating system is not enough for this.

Short peaks around 0:00: backups

Backups start at 0:00 (midnight, German time). The host compresses with pigz, a parallel variant of gzip built for speed, which briefly loads many cores heavily. That is why host load is higher at this time and steal can rise for a short while. This is known and expected. If it only affects you in this time window, you do not need to do anything. If your server runs noticeably badly then, write to us anyway and we will look at the host.

Rarely: load on the host

We overbook our hosts moderately, but never beyond peak performance. For new servers we choose the host based on its recent average load. Even so, it can rarely happen that a process on the host runs wild or that load shifts because of upgrades and changed usage by customers. In such cases we fix the problem directly on the host. In individual cases we move servers of customers who contact us to another host. Sometimes we also approach customers with permanently very high load.

You can see whether there is a disruption right now on our status page.

What to include in your ticket

  • Name or ID of the server.
  • Output of top or vmstat 1 10 including the steal column.
  • Since when the problem exists and whether you added cores or changed the package shortly before.
  • Times when the value is especially high.

Common pitfalls

  • Mixing up steal and your own load: High values at us or sy are your own processes, not steal. Use top to see which process uses the CPU.
  • Only rebooting inside the operating system: A reboot does not apply a new VM configuration. For that you need ?Stop und Start? (stop and start) in Vionity.
  • Measuring only briefly around midnight: Steal around 0:00 is the backup window and not necessarily a fault.
  • High priority ticket: High priority is meant for emergencies and gives no speed advantage.