test-definitions/blob/master/auto-test/24h-stress-test/24h-stress-test.sh

#!/bin/sh

# shellcheck disable=SC1091
#执行脚本后，就可以调用脚本中定义的函数
. ../../lib/sh-test-lib
#定义常量，这里的常量都是用双引号。
OUTPUT="$(pwd)/output"
RESULT_FILE="${OUTPUT}/result.txt"
export RESULT_FILE
# Set default values.
TESTS="stress_ng stress_oom stress_network"
#定义一个常数
DURATION=$((60 * 60 * 6))
INTERFACE="eth0"
# An valid link should be specified. Here is an example.
LINK="http://192.168.3.1/testdata/stress-network.img"
MD5="e5c834fbdaa6bfd8eac5eb9404eefdd4"
NPROC=$(nproc)
#应以一个usage函数说明调用这个脚本个个参数的作用
usage()
{
    echo "Usage: $0 [-h] [-t tests] [-d duration] [-i interface] [-l link] [-m md5]"
    echo
    echo "Options"
    echo "    -h, --help        Print this help message"
    echo "    -t, --test        Run only specified test from the following:"
    echo "                          stress_ng"
    echo "                          stress_oom"
    echo "                          stress_network"
    echo "    -d, --duration    Set test duration in seconds for each stress test"
    echo "    -i, --interface   Run network stress on the specified interface."
    echo "    -l, --link        Specify file link for download test."
    echo "    -m, --md5         Set md5 value of the file used for download test."
    echo
    echo "Examples"
    echo "    Run all stress tests with defualt settings:"
    echo "        $0"
    echo "    Set test duration for each test to 1 hour:"
    echo "        $0 -d 3600"
    echo "    Run network stress test on eth0:"
    echo "        $0 -t stress_network -i eth0"
    echo "    Run stress_ng and stress_oom:"
    echo "        $0 -t 'stress_ng stress_oom'"
    echo
}

# Parse command line arguments.
#下面这个case中的参数可以同时指定，这里用while循环分别parse.
while [ $# -gt 0 ]
do
    case $1 in
        -t|--test)
            TESTS="$2"
            ;;
        -d|--DURATION)
            DURATION="$2"
            ;;
        -i|--INTERFACE)
            INTERFACE="$2"
            ;;
        -l|--LINK)
            LINK="$2"
            ;;
        -m|--MD5)
            MD5=$2
            ;;
        -h|--help)
            usage
            exit 1
            ;;
        *)
            echo "Unknown option $*"
            usage
            exit 1
            ;;
    esac
    shift 2
done

stress_ng()
{
    workloads="cpu io fork switch vm pipe yield hdd cache sock fallocate flock affinity timer dentry urandom sem open sigq poll"
	#通过wc -w 统计有多少个单词
    workload_number=$(echo "$workloads" | wc -w)
    sub_duration=$(( DURATION / workload_number ))

    echo "CPU(s): $NPROC"
    echo "Workloads to run: $workloads"
    echo "Total stress_ng test duration: $DURATION seconds"
    echo "Test duration for each workload: $sub_duration seconds"

    count=1
    for i in $workloads
    do
        echo
        echo "[$count/$workload_number] Running $i workload..."
		#如果测试的vm的话，stress-ng这个函数的参数有所不同
        if [ "$i" = "vm" ]; then
            # mmap 64M per vm process to avoid OOM, the default is 256M.
            stress-ng --"$i" "$NPROC" --vm-bytes 64m --timeout "$sub_duration" --metrics-brief --verbose
        else
            stress-ng --"$i" "$NPROC" --timeout "$sub_duration" --metrics-brief --verbose
        fi
        check_return stress-ng-"$i"
		#count子加1
        count=$(( count + 1 ))
    done
}
#定义测试oom的函数
stress_oom()
{
	#通过free命令输出的计算mem和swap
    mem=$(free | grep Mem | awk '{print $2}')
    swap=$(free | grep Swap | awk '{print $2}')
    total_mem=$(( mem + swap ))
    vm_bytes=$(( total_mem / NPROC ))

    echo
    echo "CPU(s): $NPROC"
    echo "Total Memory: $total_mem"
    echo "Stress OOM test duration: $DURATION seconds"
    echo "About to run $NPROC stress-ng-vm instances"

    # Clear dmesg and save new output continuously to a log file.
	#清掉dmesg的输出，并把输出重定向到一个文件中
    dmesg --clear
    dmesg --follow > "${OUTPUT}/stress_oom_kern.log" 2>&1 &   # -w, --follow                wait for new messages

	#这里$!表示最后运行的后台，这里就上面重定向log的process
    kernel_log=$!
    # Disable oom-killer on the log collecting process.
    # shellcheck disable=SC2039
	#修改oom的值
    echo -17 > "/proc/${kernel_log}/oom_score_adj"
    # Disables timeout message.
	#禁止hung_task_timeout_secs
    echo 0 > /proc/sys/kernel/hung_task_timeout_secs

    # Run stress-ng-vm test to trigger oom-killer.
    # In stress-vm.c file, NO_MEM_RETRIES_MAX has been increased to 1000000000 for OOM stress test.
    echo "mmap ${vm_bytes}KB per vm process to occupy all memory to trigger oom-killer."
	#开始测试
    stress-ng --vm "$NPROC" --vm-bytes "${vm_bytes}k" --timeout "$DURATION" --metrics-brief --verbose

    # Check if oom-killer triggered.
	#杀掉之前重定向log的进程以触发oom
    kill $kernel_log
    oom_number=$(grep -c "Out of memory: Kill process" "$OUTPUT/stress_oom_kern.log")
	#通过查找输出文件中是否有"Out of memory: Kill process"的字符串还确定是否发生oom
	#-gt 表示不等于o的话，说明查找到了.
    if [ "$oom_number" -gt 0 ]; then
        echo "oom-killer activated $oom_number times within $DURATION seconds"
		#输出log，表示oom成功
        report_pass "stress-oom-test"
    else
        echo "Failed to active oom-killer."
        report_fail "stress-oom-test"
    fi
}

stress_network()
{
    echo "Stress network test duration: $DURATION"
    echo "Test interface: $INTERFACE"
    echo "File link: $LINK"
    echo "md5: $MD5"

    # Check if network set on the interface.
	#执行ip route show default 后得到ip地址
    gateway=$(ip route show default | grep -m 1 default | awk '{print $3}')
	#指定gateway，并且ping 10次.
    if ! ping -c 10 -I "$INTERFACE" "$gateway"; then
        echo "Please check network connection and rerun this script"
        exit 1
    fi

    # Check if $LINK set properly.
	#curl -O --remote-name   Write output to a file named as the remote file
    if curl -O "$LINK"; then
        echo "LINK is accessable."
		#测试成功后，删除这个文件
        rm -f stress-network.img
    else
        echo "Please download stress-network.img with the following link:"
        echo "http://testdata.validation.linaro.org/stress/stress-network.img"
        echo "And place the file on local http server, then modify 'LINK' pramater:"
        echo "    with '-l $LINK' when using script directly."
        echo "    by defining LINK paramter in definition file or test plan."
        exit 1
    fi

    # Run 'stress-ng hdd' stress in the background.
    echo "About to run 'stress-ng --hdd 1' in background"
	#在后台进程测试hdd。
    stress-ng --hdd 1 > /dev/null 2>&1 &
	#保存执行的结果到stress_ng_hdd
    stress_ng_hdd=$!
	#睡眠10s
    sleep 10
	#测试结束的时间
    end=$(( $(date +%s) + DURATION ))
    iteration=0
	#现在的时间小于结束的时间，则执行while循环
    while [ "$(date +%s)" -lt "$end" ]
    do
        echo
        echo "Running stress_network iteration $iteration"
		#如果没有找到stress-ng-hdd 这个进程，则重新开始这个进程的执行，pgrep 用于查找进程.
        if ! pgrep -l "stress-ng-hdd"; then
            echo "'stress-ng --hdd 1' is dead, restarting..."
            stress-ng --hdd 1 > /dev/null 2>&1 &
            stress_ng_hdd=$!
        else
            echo "'stress-ng --hdd 1' is running in background"
        fi

        # Network enable/disable test.
		#down掉网口
        ip link set "$INTERFACE" down
        sleep 15
		#查询网口是否已经给down了
        ip link show dev "$INTERFACE" | grep "state DOWN"
        check_return "network-disable-$iteration"
		#up 网口
        ip link set "$INTERFACE" up
        sleep 15
        ip link show dev "$INTERFACE" | grep "state UP"
        check_return "network-enable-$iteration"

        # Check if IP obtained.
		#检查是否可以获取ip 地址
        dhclient "$INTERFACE" > /dev/null 2>&1 || true
        ip=$(ip addr show "$INTERFACE" | grep -w inet | awk '{print $2}' | awk -F'/' '{print $1}')
		#test -n 用于检查后面的字符串是否为null.
        test -n "$ip"
		#调用函数
        check_return "network-ip-check-$iteration"

        # File download test.
		#test -e 表示检查文件是否存在，如果存在的话，则删除
        test -e stress-network.img && rm -rf stress-network.img
		#指定ip地址下载
        curl -O --interface "$ip" "$LINK"
        check_return "file-download-$iteration"
		#计算md5的值
        local_md5=$(md5sum stress-network.img | awk '{print $1}')
		#判断这两个md5值是否相等
        test "$local_md5" = "$MD5"
        check_return "file-md5-check-$iteration"
		#删除这个文件
        rm -rf stress-network.img
		#计数变量自加1
        iteration=$(( iteration + 1 ))
    done
	#结束掉这个进程
    kill "$stress_ng_hdd"
}

## Setup environment and run tests.
#检查是否root 用户，如果不是root用户输出错误日志
! check_root && error_msg "You need to be root to run this test!"
#如果已经存在目录的话，则把这个命令移动到李哥新的命令中，如果不存在就新建目录
[ -d "${OUTPUT}" ] && mv "${OUTPUT}" "${OUTPUT}_$(date +%Y%m%d%H%M%S)"
mkdir -p "${OUTPUT}"
#如果没有安装curl的话，按照那个curl
which curl || install_deps "curl"
#如果不存在stress-ng的话
if ! which stress-ng; then
        echo "stress-ng not found, installing it ..."
		#执行dist_name函数输出发行版的名字
        dist_name
        # shellcheck disable=SC2154
        case "${dist}" in
		#如果发行版是Ubuntu 或者debian的话，则看庄下面这些包
            debian|ubuntu)
                install_deps "git build-essential libaio-dev libapparmor-dev libattr1-dev libbsd-dev libcap-dev libgcrypt11-dev libkeyutils-dev libsctp-dev zlib1g-dev"
				#clone git仓库
                git clone git://kernel.ubuntu.com/cking/stress-ng.git
                (
                    cd stress-ng || exit
                    # Use a known good release.
					#切换到具体的岑智
                    git checkout V0.05.21 -b V0.05.21
                    # Set NO_MEM_RETRIES_MAX to 1000000000 for long time stress OOM test.
					#在stress-vm.c 中通过sed -i 插入两个宏定义
                    sed -i "s/#define NO_MEM_RETRIES_MAX$(printf '\t')(100)/#define NO_MEM_RETRIES_MAX$(printf '\t')(1000000000)/" stress-vm.c
					#build 并安装
                    make && make install
                )
                ;;
            *)
                warn_msg "Unsupported distro: ${dist}! Package installation skipped."
                ;;
        esac
fi

# Run tests.
for i in $TESTS
do
	#分别执行TEST中定义的三个函数.
    "$i" 2>&1 | tee "${OUTPUT}/${i}.log"
done