用于检查内存使用率（以百分比表示）的linux命令
$ free -t | awk 'NR == 2 {printf(Current Memory utilization is : %.2f%), $3/$2*100}'
or
$ free -t | awk 'FNR == 2 {printf(Current Memory utilization is : %.2f%), $3/$2*100}'
Current Memory utilization is : 20.42%
用于检查内存使用率（以百分比表示）的linux命令
$ free -t | awk 'NR == 2 {printf(Current Memory utilization is : %.2f%), $3/$2*100}'
or
$ free -t | awk 'FNR == 2 {printf(Current Memory utilization is : %.2f%), $3/$2*100}'
Current Memory utilization is : 20.42%