linux内存监控

1. 内存申请顺序：free-->cache-->buffer-->swap

1、

#!/bin/bash
#
total=$(free -m | sed -n '2p' | awk '{print $2}')
used=$(free -m | sed -n '2p' | awk '{print $3}')
free=$(free -m | sed -n '2p' | awk '{print $4}')
shared=$(free -m | sed -n '2p' | awk '{print $5}')
buff=$(free -m | sed -n '2p' | awk '{print $6}')
cached=$(free -m | sed -n '2p' | awk '{print $7}')
rate=`echo "scale=2;$used/$total" | bc | awk -F. '{print $2}'`
echo -e "total\tused\tfree\tshared\tbuffer\tavailable"
echo -e "${total}M\t${used}M\t${free}M\t${shared}M\t${buff}M\t${cached}M\nrate:${rate}%"

2、
head -2 /proc/meminfo |awk 'NR==1{t=$2}NR==2{f=$2;print(t-f)*100/t}'
39.6309

3、

memory_use() {
memory_used=`head -2 /proc/meminfo | awk 'NR==1{t=$2}NR==2{f=$2;print(t-f)*100/t"%"}'`
memory_cache=`head -5 /proc/meminfo | awk 'NR==1{t=$2}NR==5{c=$2;print c*100/t"%"}'`
memory_buffer=`head -4 /proc/meminfo | awk 'NR==1{t=$2}NR==4{d=$2;print d*100/t"%"}'`
 
echo "memory_used: " $memory_used
echo "memory_cache: " $memory_cache
echo "memory_buffer: " $memory_buffer
echo 
echo -e "memory_use: $memory_used\t cache: $memory_cache\t buffer: $memory_buffer"
}
memory_use

4、

memory_use(){
memory_used=`head -2 /proc/meminfo |awk 'NR==1{t=$2}NR==2{f=$2;print(t-f)*100/t"%"}'`
memory_cache=`head -5 /proc/meminfo |awk 'NR==1{t=$2}NR==5{c=$2;print c*100/t"%"}'`
memory_buffer=`head -4 /proc/meminfo |awk 'NR==1{t=$2}NR==4{b=$2;print b*100/t"%"}'`

echo -e "memory_used:$memory_used\tmemory_buffer:$memory_buffer\tmemory_cache:$memory_cache"

}
memory_use