新增learn-kubernetes（https://github.com/yyong-brs/learn-kubernetes）相关文件

learn/learn-kubernetes-master/kiamol/ch19/docker-images/stress/Dockerfile

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+FROM debian:buster-slim
+
+RUN apt-get update \
+ && apt-get install -y --no-install-recommends \
+    bc \
+    stress \
+ && rm -rf /var/lib/apt/lists/*
+
+ ENV MEMORY_STRESS_MB="50" \
+     MEMORY_STRESS_FACTOR="" \
+     STRESS_HANG="3540" \
+     STRESS_TIMEOUT="3600"
+
+COPY ./stress-memory.sh .
+
+CMD chmod +x ./stress-memory.sh && ./stress-memory.sh

learn/learn-kubernetes-master/kiamol/ch19/docker-images/stress/stress-memory.sh

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+#!/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))
+
+if [ -n "$MEMORY_STRESS_FACTOR" ]; then
+    stress_mb=$(echo "$memory_available_in_mb * $MEMORY_STRESS_FACTOR" | bc -l)    
+else
+    stress_mb=$MEMORY_STRESS_MB
+fi
+stress_mb_int="$(printf '%d' $stress_mb 2>/dev/null)"
+
+echo '----------------'
+echo "Memory available: ${memory_available_in_mb}M"
+echo "Stress factor: ${MEMORY_STRESS_FACTOR}"
+echo "Stressing memory: ${stress_mb_int}M"
+echo '----------------'
+
+exec /bin/sh -c "trap : TERM INT; (stress -q --vm 1 --vm-bytes ${stress_mb_int}M --vm-hang $STRESS_HANG -t $STRESS_TIMEOUT) & wait"