由于Centos7和6的系统变化挻大的，所以先看看Centos7的内存信息是怎么样的。
系统版本：
[root@docker ~]# cat /etc/redhat-release CentOS Linux release 7.2.1511 (Core) [root@docker ~]#
查看内存信息：其实只需要关注前5行即可；
[root@docker ~]# cat /proc/meminfo MemTotal: 2049248 kBMemFree: 85408 kBMemAvailable: 1061812 kBBuffers: 138044 kBCached: 885028 kBSwapCached: 33308 kBActive: 881088 kBInactive: 832516 kBActive(anon): 315948 kBInactive(anon): 375464 kBActive(file): 565140 kBInactive(file): 457052 kBUnevictable: 0 kBMlocked: 0 kBSwapTotal: 524284 kBSwapFree: 377836 kBDirty: 24 kBWriteback: 0 kBAnonPages: 659500 kBMapped: 71544 kBShmem: 876 kBSlab: 160772 kBSReclaimable: 123148 kBSUnreclaim: 37624 kBKernelStack: 7408 kBPageTables: 20580 kBNFS_Unstable: 0 kBBounce: 0 kBWritebackTmp: 0 kBCommitLimit: 1548908 kBCommitted_AS: 2998548 kBVmallocTotal: 34359738367 kBVmallocUsed: 156648 kBVmallocChunk: 34359541760 kBHardwareCorrupted: 0 kBAnonHugePages: 434176 kBHugePages_Total: 0HugePages_Free: 0HugePages_Rsvd: 0HugePages_Surp: 0Hugepagesize: 2048 kBDirectMap4k: 73664 kBDirectMap2M: 2023424 kBDirectMap1G: 0 kB[root@docker ~]# [root@docker ~]# free -m total used free shared buff/cache availableMem: 2001 762 81 0 1156 1035Swap: 511 142 369[root@docker ~]#
内存使用率的计算：mem_used=MemTotal-MemFree-Buffers
python 代码：
#/usr/bin/env python import time import pymysql as mysql db = mysql.connect(user='dba',passwd='123456',db='memory',host='localhost') db.autocommit(True) cur = db.cursor() def getMem(): f = open('/proc/meminfo') total = int(f.readline().split()[1]) free = int(f.readline().split()[1]) MemAvailable = f.readline().split() cache = int(f.readline().split()[1]) mem_use = total-free-cache t = time.time() sql = 'insert into memory(memory,time) values(%s,%s)' %(mem_use/1024,t) cur.execute(sql) #print mem_use print ('ok') while True: time.sleep(1) getMem()
安装pymysql模块
pip install pymysql
创建数据库以及表：
MariaDB [(none)]> create database memory charset=utf8;MariaDB [(none)]> use memory;MariaDB [(none)]> CREATE TABLE `memory` ( `memory` int(11) DEFAULT NULL, `time` int(11) DEFAULT NULL ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;授权用户MariaDB [(none)]> grant all on *.* to dba@'localhost' identified by '123456';MariaDB [(none)]> flush privileges;
执行python代码，每隔一秒就会打印一个ok到终端，然后在Mysql里查询一下；
MariaDB [memory]> select * from memory limit 5;+--------+------------+| memory | time |+--------+------------+| 1775 | 1513906229 || 1775 | 1513906230 || 1775 | 1513906231 || 1775 | 1513906232 || 1775 | 1513906233 |+--------+------------+5 rows in set (0.00 sec)
注：Mysql的表只用了两个字段，一个内存使用率，这个值是以兆为单位的，另一个就是时间了。
MariaDB [(none)]> use memory;Reading table information for completion of table and column namesYou can turn off this feature to get a quicker startup with -ADatabase changedMariaDB [memory]> show create table memory\G*************************** 1. row *************************** Table: memoryCreate Table: CREATE TABLE `memory` ( `memory` int(11) DEFAULT NULL, `time` int(11) DEFAULT NULL) ENGINE=InnoDB DEFAULT CHARSET=utf8mb41 row in set (0.00 sec)MariaDB [memory]>