Linux CPU stress
Linux CPU stress fault applies stress on the CPU of the target Linux machines for a specific duration.
Use cases
- Induces CPU stress on the target Linux machines.
- Simulates a lack of CPU for processes running on the application, which degrades their performance.
- Simulates slow application traffic or exhaustion of the resources, leading to degradation in the performance of processes on the machine.
note
- This fault can be executed on Ubuntu 16 or higher, Debian 10 or higher, CentOS 7 or higher, RHEL 7 or higher, Fedora 30 or higher, and openSUSE LEAP 15.4 or higher.
- The
linux-chaos-infrastructure
systemd service should be in an active state, and the infrastructure should be inCONNECTED
state.
Fault permissions
The fault uses the root
Linux user and root
user group.
External packages
This fault uses stress-ng
, which is installed as part of the infrastructure installation.
Optional tunables
Tunable | Description | Notes |
---|---|---|
load | Percentage load to be exerted on a single CPU core. | Default: 100 %. |
workers | Number of worker processes to start. Corresponds to the number of CPU cores to consume. | Default: 1. |
duration | Duration through which chaos is injected into the target resource. Should be provided in [numeric-hours]h[numeric-minutes]m[numeric-seconds]s format. | Default: 30s . Examples: 1m25s , 1h3m2s , 1h3s |
rampTime | Period to wait before and after injecting chaos. Should be provided in [numeric-hours]h[numeric-minutes]m[numeric-seconds]s format. | Default: 0s . Examples: 1m25s , 1h3m2s , 1h3s |
Workers
The workers
input variable utilizes a specific number of workers for the CPU stress fault.
The following YAML snippet illustrates the use of this input variable:
# workers to utilize
apiVersion: litmuchaos.io/v1alpha1
kind: LinuxFault
metadata:
name: linux-cpu-stress
labels:
name: cpu-stress
spec:
stressChaos/inputs:
workers: 1
load: 100
Load percentage
The load
input variable exerts the CPU load (in percentage) per core.
The following YAML snippet illustrates the use of this input variable:
# percentage load to exert per core
apiVersion: litmuchaos.io/v1alpha1
kind: LinuxFault
metadata:
name: linux-cpu-stress
labels:
name: cpu-stress
spec:
stressChaos/inputs:
workers: 3
load: 70