CPU监控脚本未正确触发

Question

我想知道有没有人能帮我解释一下这不能正常触发的原因

HOSTNAME=`hostname -s`
LOAD=25.00
CAT=/bin/cat
MAILFILE=/home/jboss/monitor.mail
MAILER=/bin/mail
mailto="bob@bob.bob"
CPU_LOAD=`sar -P ALL 1 10 |grep 'Average.*all' |awk -F" " '{print 100.0 -$NF}'`
if [[ $CPU_LOAD > $LOAD ]];
then
PROC=`ps -eo pcpu,pid -o comm= | sort -k1 -n -r | head -1`
echo -e "Please check processes on ${HOSTNAME} the value of cpu load is $CPU_LOAD%.
Highest process is: $PROC" > $MAILFILE
$CAT $MAILFILE | $MAILER -s "CPU Load is on ${HOSTNAME} is $CPU_LOAD %" $mailto
fi

这似乎是工作正常的sar和ps，但我仍然收到电子邮件的警报，如CPU负载是3.18%。除非我错过了一些它不应该触发的东西，除非负载大于25%。

但是，如果负载大于2.5%，似乎会做更多的事情，有什么建议吗？

谢谢

Answer 1

而不是使用：

if [[ $CPU_LOAD > $LOAD ]];then

您必须使用

if [[ $CPU_LOAD -gt $LOAD ]]; then

Answer 2

Bash只处理整数，所以要使用更高的精度，可以这样做：

cpu_limit=25
# read the 5min load-average straight from the special file on /proc
read -r _ load_avg _ </proc/loadavg
# multiply by 100 for precision
load_avg=$(bc <<<"scale=0; $load_avg * 100 / 1")
# compare numbers with (( )) instead
if (( load_avg > cpu_limit )); then
   ...
fi

Answer 3

试试这段代码--(测试过了--工作正常)

$ cat f.sh
HOSTNAME=$(hostname -s)
LOAD=25.00
MAILFILE=$HOME/a.txt
MAILER=/bin/mailx
mailto="vipinkumarr89@gmail.com"
CPU_LOAD=$(sar -P ALL 1 10 |grep 'Average.*all' |awk -F" " '{print 100.0 -$NF}')
if [[ $CPU_LOAD > $LOAD ]];then
{
PROC=$(ps -eo pcpu,pid -o comm= | sort -k1 -n -r | head -1)
echo -e "Please check processes on ${HOSTNAME} the value of cpu load is $CPU_LOAD%.
Highest process is: $PROC" > $MAILFILE
cat $MAILFILE | $MAILER -s "CPU Load is on ${HOSTNAME} is $CPU_LOAD %" $mailto
}
fi