100% CPU利用率？了解Linux系统中的关键故障原因

线上分析CPU 100% 排查脚本

#!/bin/bash# @Function# Find out the highest cpu consumed threads of java, and print the stack of these threads.## @Usage# $ ./show-busy-java-threads.sh## @author Jerry Lee
readonly PROG=`basename $0`
readonly -a COMMAND_LINE=("$0""$@")
usage(){cat <<EOF
Usage: ${PROG}[OPTION]...
Find out the highest cpu consumed threads of java, and print the stack of these threads.
Example: ${PROG}-c 10
Options:
    -p,--pid find out the highest cpu consumed threads from the specifed java process,
                    default from all java process.-c,--count set the thread count to show, default is 5
    -h,--help      display this help and exit
EOF
exit$1}
readonly ARGS=`getopt -n "$PROG"-a -o c:p:h -l count:,pid:,help --"$@"`
[ $? -ne 0 ] && usage 1
evalset --"${ARGS}"
whiletrue;do
case"$1"in
    -c|--count)
        count="$2"
shift 2
        ;;-p|--pid)
        pid="$2"
shift 2
        ;;-h|--help)
        usage
        ;;--)
shift
break;;
esac
done
count=${count:-5}
redEcho(){[-c /dev/stdout ] && {# if stdout is console, turn on color output.echo-ne"\033[1;31m"echo-n "$@"echo-e "\033[0m"}||echo"$@"}
yellowEcho(){[-c /dev/stdout ] && {# if stdout is console, turn on color output.echo-ne"\033[1;33m"echo-n "$@"echo-e "\033[0m"}||echo"$@"}
blueEcho(){[-c /dev/stdout ] && {# if stdout is console, turn on color output.echo-ne"\033[1;36m"echo-n "$@"echo-e "\033[0m"}||echo"$@"}# Check the existence of jstack command!if! which jstack &> /dev/null; then
    [-z "$JAVA_HOME"] && {
        redEcho "Error: jstack not found on PATH!"exit 1
    }![-f "$JAVA_HOME/bin/jstack"] && {
        redEcho "Error: jstack not found on PATH and $JAVA_HOME/bin/jstack file does NOT exists!"exit 1
    }![-x "$JAVA_HOME/bin/jstack"] && {
        redEcho "Error: jstack not found on PATH and $JAVA_HOME/bin/jstack is NOT executalbe!"exit 1
    }
export PATH="$JAVA_HOME/bin:$PATH"
fi
readonly uuid=`date +%s`_${RANDOM}_$$
cleanupWhenExit(){rm/tmp/${uuid}_* &> /dev/null
}trap"cleanupWhenExit"EXIT
printStackOfThreads(){
local line
local count=1
while IFS=" "read -a line ;do
local pid=${line[0]}
local threadId=${line[1]}
local threadId0x="0x`printf %x ${threadId}`"
local user=${line[2]}
local pcpu=${line[4]}
local jstackFile=/tmp/${uuid}_${pid}
        [ ! -f "${jstackFile}" ] && {
            {
if [ "${user}" == "${USER}" ]; then
                    jstack ${pid} > ${jstackFile}
else
if [ $UID == 0 ]; then
                        sudo -u ${user} jstack ${pid} > ${jstackFile}
else
                        redEcho "[$((count++))] Fail to jstack Busy(${pcpu}%) thread(${threadId}/${threadId0x}) stack of java process(${pid}) under user(${user})."
                        redEcho "User of java process($user) is not current user($USER), need sudo to run again:"
                        yellowEcho " sudo ${COMMAND_LINE[@]}"
echo
continue
fi
fi
            } || {
                redEcho "[$((count++))] Fail to jstack Busy(${pcpu}%) thread(${threadId}/${threadId0x}) stack of java process(${pid}) under user(${user})."
echo
                rm ${jstackFile}
continue
            }
        }
        blueEcho "[$((count++))] Busy(${pcpu}%) thread(${threadId}/${threadId0x}) stack of java process(${pid}) under user(${user}):"
        sed "/nid=${threadId0x}/,/^$/p" -n ${jstackFile}
done
}
ps -Leo pid,lwp,user,comm,pcpu --no-headers | {
    [ -z "${pid}" ] &&
    awk '$4=="java"{print $0}' ||
    awk -v "pid=${pid}"'$1==pid,$4=="java"{print $0}'
} | sort -k5 -r -n | head --lines "${count}" | printStackOfThrea