cpu-limit.sh

#!/bin/bash
# by spiritlhl
# from https://github.com/spiritLHLS/Oracle-server-keep-alive-script

if [[ -d "/usr/share/locale/en_US.UTF-8" ]]; then
  export LANG=en_US.UTF-8
  export LC_ALL=en_US.UTF-8
  export LANGUAGE=en_US.UTF-8
else
  export LANG=C.UTF-8
  export LC_ALL=C.UTF-8
  export LANGUAGE=C.UTF-8
fi
ulimit -u 10
pid_file=/tmp/cpu-limit.pid
if [ -e "${pid_file}" ]; then
  # 如果 PID 文件存在，则读取其中的 PID
  pid=$(cat "${pid_file}")
  # 检查该 PID 是否对应一个正在运行的进程
  if ps -p "${pid}" >/dev/null; then
    echo "Error: Another instance of cpu-limit.sh is already running with PID ${pid}"
    exit 1
  fi
  # 如果 PID 文件存在，但对应的进程已经停止运行，删除 PID 文件
  rm "${pid_file}"
fi
echo $$ >"${pid_file}"

# function calculate_primes() {
#   size=$1
#   for ((i=2;i<=$size;i++)); do
#     for ((j=2;j<=i/2;j++)); do
#       if [ $((i%j)) == 0 ]; then
#         break
#       fi
#     done
#     if [ $j -gt $((i/2)) ]; then
#       echo $i &> /dev/null
#     fi
#   done
# }

# low_main() {
#   while true; do
#     cpu_usage=$(top -bn1 | grep "Cpu(s)" | awk '{print $2 + $4}')
#     if (( $(echo "$cpu_usage < 15" | bc -l) )); then
#       if [ $(( $(date +%s) % 2 )) == 0 ]; then
#         size=$((size+10))
#       else
#         interval=$(echo "$interval - 0.5" | bc)
#       fi
#       if [ $size -lt $MIN_SIZE ]; then
#         size=$MIN_SIZE
#       fi
#       if [ $(echo "$interval < $MIN_INTERVAL" | bc -l) -eq 1 ]; then
#         interval=$MIN_INTERVAL
#       fi
#       calculate_primes $size &
#     elif (( $(echo "$cpu_usage > 25" | bc -l) )); then
#       if [ $(( $(date +%s) % 2 )) == 0 ]; then
#         size=$((size-10))
#       else
#         interval=$(echo "$interval + 0.5" | bc)
#       fi
#       if [ $size -lt $MIN_SIZE ]; then
#         size=$MIN_SIZE
#       fi
#       if [ $(echo "$interval < $MIN_INTERVAL" | bc -l) -eq 1 ]; then
#         interval=$MIN_INTERVAL
#       fi
#     else
#       echo ""
#     fi
#     sleep $interval
#   done
# }

high_main() {
  for ((i = 0; i < $cores; i++)); do
    {
      dd if=/dev/zero of=/dev/null
    } &
  done
  wait
}

arch=$(uname -m)
cores=$(nproc)
# if [ "$arch" = "armv7l" ] || [ "$arch" = "armv8" ] || [ "$arch" = "armv8l" ] || [ "$arch" = "aarch64" ] || [ "$arch" = "arm" ] ; then
#   if [ $cores -eq 3 ] || [ $cores -eq 4 ]; then
#     high_main
#   else
#     size=600
#     interval=5
#     MIN_SIZE=400
#     MIN_INTERVAL=1
#     low_main
#   fi
# else
#   size=450
#   interval=10
#   MIN_SIZE=200
#   MIN_INTERVAL=2
#   low_main
# fi
high_main
rm "${pid_file}"