服务器运行CPU/内存保护

1、调整内核参数，避免过度分配内存

1.1、编辑 /etc/sysctl.conf

#严格控制内存分配：0=启发式，1=总是过载，2=禁止过载（推荐）

vm.overcommit_memory = 2

#当 overcommit_memory=2 时，允许分配的地址空间不超过swap+RAM*比例

vm.overcommit_ratio = 90

1.2、执行 sysctl -p 生效

2、编辑脚本实现，定时（crontab）Centos7当整体CPU使用率连续5分钟（可配置）超过99%时，自动终止除操作系统核心进程外CPU占用最高的3个进程，并记录kill进程的详细信息。

#!/bin/bash

配置参数

LOG_FILE="/home/sunxy/cpukill/cpu_monitor.log"

COUNT_FILE="/home/sunxy/cpukill/cpu_monitor_count.txt"

THRESHOLD=99 # CPU使用率阈值

DURATION=5 # 连续超过阈值的分钟数

MAX_PROCESSES=3 # 最多终止的进程数

核心进程列表（根据CentOS 7系统核心进程调整）

CORE_PROCESSES=("systemd" "kthreadd" "ksoftirqd" "rcu_sched" "rcu_bh" "migration" "watchdog" "kworker" "kswapd" "vmstat" "journald" "sshd" "crond" "rsyslogd" "network" "udevd")

确保日志文件和计数文件目录存在

mkdir -p "(dirname"(dirname "(dirname"LOG_FILE")"

mkdir -p "(dirname"(dirname "(dirname"COUNT_FILE")"

记录日志函数

log_message() {

local message="1"echo"1" echo "1"echo"(date '+%Y-%m-%d %H:%M:%S') - message">>"message" >> "message">>"LOG_FILE"

echo "$message"

}

检查是否为核心进程

is_core_process() {

local process_name="1"forcoreprocin"1" for core_proc in "1"forcoreprocin"{CORE_PROCESSES $@$ }"; do

if $\[ "processname"==∗"process_name" == \*"processname"==∗"core_proc"\*$ ]; then

return 0

done

return 1

}

读取计数

read_count() {

if $-f "COUNTFILE"$ ;thencat"COUNT_FILE" ]; then cat "COUNTFILE"];thencat"COUNT_FILE"

else

echo 0

}

写入计数

write_count() {

local count="1"echo"1" echo "1"echo"count" > "$COUNT_FILE"

}

主监控函数

main() {

log_message "CPU监控脚本执行"

复制代码

# 读取当前计数
high_cpu_count=$(read_count)

# 获取整体CPU使用率（使用top命令，过滤掉空闲CPU）
cpu_usage=$(top -bn1 | grep "Cpu(s)" | sed "s/.*, *\([0-9.]*\)%* id.*/\1/" | awk '{print 100 - $1}')

# 四舍五入到整数
cpu_usage_int=$(printf "%.0f" "$cpu_usage")

log_message "当前CPU使用率: ${cpu_usage_int}% (阈值: ${THRESHOLD}%)"

# 检查是否超过阈值
if [ "$cpu_usage_int" -ge "$THRESHOLD" ]; then
    high_cpu_count=$((high_cpu_count + 1))
    log_message "CPU使用率超过阈值，连续计数: ${high_cpu_count}/${DURATION}"
    write_count "$high_cpu_count"
else
    high_cpu_count=0
    log_message "CPU使用率低于阈值，重置计数"
    write_count "$high_cpu_count"
fi

# 连续达到指定分钟数，执行清理操作
if [ "$high_cpu_count" -ge "$DURATION" ]; then
    log_message "CPU使用率连续${DURATION}分钟超过${THRESHOLD}%，开始清理进程"
    
    # 获取CPU占用最高的进程（排除核心进程）
    top_processes=$(ps aux --sort=-%cpu | awk 'NR>1 {print $1 " " $2 " " $3 " " $11}' | head -20)
    
    # 筛选非核心进程并取前N个
    kill_count=0
    while read -r line; do
        if [ "$kill_count" -ge "$MAX_PROCESSES" ]; then
            break
        fi
        
        user=$(echo "$line" | awk '{print $1}')
        pid=$(echo "$line" | awk '{print $2}')
        cpu=$(echo "$line" | awk '{print $3}')
        cmd=$(echo "$line" | awk '{print $4}')
        
        # 检查是否为核心进程
        if ! is_core_process "$cmd"; then
            log_message "准备终止进程: PID=$pid, USER=$user, CPU=$cpu%, COMMAND=$cmd"
            
            # 记录进程详细信息
            process_detail=$(ps -p "$pid" -o pid,ppid,user,group,cmd,%cpu,%mem,etime,args --no-headers)
            log_message "进程详细信息: $process_detail"
            
            # 终止进程
            if kill -9 "$pid"; then
                log_message "成功终止进程: PID=$pid"
                kill_count=$((kill_count + 1))
            else
                log_message "终止进程失败: PID=$pid"
            fi
        fi
    done <<< "$top_processes"
    
    # 重置计数
    high_cpu_count=0
    write_count "$high_cpu_count"
    log_message "清理完成，共终止 ${kill_count} 个进程"
fi

}

执行主函数

main