Stress deployment for testing limits of kubernetes nodes

memory-available.sh

#!/bin/bash
#!/usr/bin/env bash

# This script reproduces what the kubelet does
# to calculate memory.available relative to root cgroup.

# current memory usage
memory_capacity_in_kb=$(cat /proc/meminfo | grep MemTotal | awk '{print $2}')
memory_capacity_in_bytes=$((memory_capacity_in_kb * 1024))
memory_usage_in_bytes=$(cat /sys/fs/cgroup/memory/memory.usage_in_bytes)
memory_total_inactive_file=$(cat /sys/fs/cgroup/memory/memory.stat | grep total_inactive_file | awk '{print $2}')

memory_working_set=${memory_usage_in_bytes}
if [ "$memory_working_set" -lt "$memory_total_inactive_file" ];
then
    memory_working_set=0
else
    memory_working_set=$((memory_usage_in_bytes - memory_total_inactive_file))
fi

memory_available_in_bytes=$((memory_capacity_in_bytes - memory_working_set))
memory_available_in_kb=$((memory_available_in_bytes / 1024))
memory_available_in_mb=$((memory_available_in_kb / 1024))

echo "memory.capacity_in_bytes $memory_capacity_in_bytes"
echo "memory.usage_in_bytes $memory_usage_in_bytes"
echo "memory.total_inactive_file $memory_total_inactive_file"
echo "memory.working_set $memory_working_set"
echo "memory.available_in_bytes $memory_available_in_bytes"
echo "memory.available_in_kb $memory_available_in_kb"
echo "memory.available_in_mb $memory_available_in_mb"

stress.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: stress
  namespace: default
spec:
  replicas: 1
  selector:
    matchLabels:
      foo: bar
  template:
    metadata:
      labels:
        foo: bar
    spec:
      nodeSelector:
        # Modify this to be whatever Node you want to deploy to
        kubernetes.io/hostname: ip-10-0-1-146.us-west-2.compute.internal
      containers:
      - image: camelcasenotation/stress:latest
        name: stress
        command: ["sh", "-c"]
        args: ["stress -m 1 --vm-bytes 6000M --vm-hang 0 --timeout 180s"]
        resources:
          requests:
            memory: 100Mi