8月 03

bash 产生随机数

  使用bash产生n位的随机数。测试中为产生8位。

#!/bin/bash
# -------------------------------
# Filename:    test.sh
# Revision:    1.0
# Date:        2013-08-01
# Author:      simonzhang
# Email:       simon-zzm@163.com
# Description: 
# -------------------------------

function randnum()
{
    di=(0 1 2 3 4 5 6 7 8 9 \
        a b c d e f g h i j k l m n o p q r s t u v w x y z \
        A B C D E F G H I G K L M N O P Q R S T U V W X Y Z \
        ~ ! ^ _)
    for(( i=0; i<$1; i++))
    do
        num=$num`echo -n ${di[$RANDOM % ${#di[*]}]}`
    done
    echo $num
}

get=$(randnum 8)
echo $get

bash产生n位随机数

6月 07

python 对字符串的加密解密

  需求是是要将密码存在数据库里,所以要加密解密是可逆的,在数据库里不要有特殊字符,防止数据库备份和恢复中出错。
  安装PyCrypto,可以用AES和DES。我使用DES加解密。加密后将密文转为16进制,在入库。测试代码如下。

#!/bin/python
#-*- coding:utf-8 -*-
# Filename:
# Revision:    
# Date:        2013-06-07
# Author:      simonzhang
# web:         www.simonzhang.net
# Email:       simon-zzm@163.com
### END INIT INFO
# easy_install PyCrypto
from binascii import b2a_hex, a2b_hex
from Crypto.Cipher import DES
key = '12345678' #长度必须是8位的
text = 'simonzhang.net  '  #长度必须是8的倍数,我用空格补的
# 实例化
obj = DES.new(key)
# 加密
cryp = obj.encrypt(text)
pass_hex = b2a_hex(cryp)
print pass_hex
print '=' * 20
# 解密
get_cryp = a2b_hex(pass_hex)
after_text = obj.decrypt(get_cryp)
print after_text

测试代码

5月 09

raspberry pi 测试pypy 切割图片效率

为了方便安装pypy的第三方库,首先安装pip。
$ curl -O http://python-distribute.org/distribute_setup.py
$ curl -O https://raw.github.com/pypa/pip/master/contrib/get-pip.py
$ sudo pypy distribute_setup.py
$ sudo pypy get-pip.py

首先找了一个3M(3072×2304)的图片,缩小为300×300的大小
脚本:

# -*- coding:utf-8 -*-
# -------------------------------
# Filename:    .py
# Revision:    1.0
# Date:        2013-05-08
# Author:      simonzhang
# Web:         www.simonzhang.net
# Email:       simon-zzm@163.com
# -------------------------------


from PIL import Image


def main():
    get_data = Image.open('test.jpg')
    tmp = get_data.resize((300, 300),)
    tmp.save('test1.jpg', 'JPEG', quality=75)


if __name__ == '__main__':
    main()

在pypy上装PIL
$ sudo /usr/lib/pypy-upstream/bin/pip install PIL

运行脚本报错如下:

File “/usr/lib/pypy-upstream/site-packages/PIL/Image.py”, line 1290, in resize
self.load()
File “/usr/lib/pypy-upstream/site-packages/PIL/ImageFile.py”, line 189, in load
d = Image._getdecoder(self.mode, d, a, self.decoderconfig)
File “/usr/lib/pypy-upstream/site-packages/PIL/Image.py”, line 385, in _getdecoder
raise IOError(“decoder %s not available” % decoder_name)
IOError: decoder jpeg not available

不能调用系统库,之前在处理过这种问题http://www.simonzhang.net/?p=435
但是pypy比较复杂,兼容有问题。直接删除PIL,使用pillow。Pillow基础就是PIL只是兼容性强,更利于推广。
$ sudo /usr/lib/pypy-upstream/bin/pip uninstall PIL

$ sudo /usr/lib/pypy-upstream/bin/pip install pillow

注意必须使用
from PIL import Image

否则会报错
File “/usr/lib/pypy-upstream/site-packages/PIL/Image.py”, line 2020, in open
raise IOError(“cannot identify image file”)
IOError: cannot identify image file

在安装完pillow后没有产生PIL.pth文件,直接手动写一个。
$ sudo vim /usr/lib/pypy-upstream/site-packages/PIL.pth
内容是:PIL。

开始测试

time python cut_pic.py

real 0m2.841s
user 0m2.630s
sys 0m0.200s

time pypy cut_pic.py

real 0m5.144s
user 0m4.870s
sys 0m0.230s

图片产生大小如下
-rw-r–r– 1 pi pi 3588203 5月 8 16:02 test.jpg
-rw-r–r– 1 pi pi 21907 5月 8 16:10 test_pypy.jpg
-rw-r–r– 1 pi pi 21907 5月 8 16:09 test_python.jpg

直接使用python的效果更佳,不清楚原因。之后有版本升级了再做测试。

4月 18

监控mysql从机同步状态脚本

  mysql数据库主从运行。为了知道从机的同步情况,写了个脚本,放在crontab中,如果同步出错,则邮件报警。去年写的,放上来做个备忘。

#!/usr/local/bin/python
# -------------------------------------------------------------------------------
# Filename:    .py
# Revision:    1.0
# Date:        2012-03-20
# Author:      simonzhang
# Web:         www.simonzhang.net
# Email:       simon-zzm@163.com
# -------------------------------------------------------------------------------
import os
import pexpect
import time
import smtplib
from email.mime.text import MIMEText

#### base se
mysql_bin = '/mysql5/bin/mysql'
mysql_user = ''
mysql_pass = ''
mail_host = 'smtp.exmail.qq.com'
mail_user = 'XXX@XXX.net'
mail_pwd = 'XXXX'
mail_to = "xxxxx@xxx.com"
####

def mail_warn(error_ip):
    content = 'IP %s mysql slave is error!'%error_ip
    msg = MIMEText(content)
    msg['From'] = mail_user
    msg['Subject'] = 'mysql warnning %s'%error_ip
    msg['To'] = mail_to
    try:
        s = smtplib.SMTP()
        s.connect(mail_host)
        s.login(mail_user,mail_pwd)
        s.sendmail(mail_user,[mail_to],msg.as_string())
        s.close()
    except Exception ,e:
        print e

def main():
    status = os.popen("%s -u%s -p%s -e 'show slave status\G'"%
                      (mysql_bin,mysql_user,mysql_pass)).read() 
    io_status = status[status.find('Slave_IO_Running: ')+18]
    sql_status = status[status.find('Slave_SQL_Running: ')+19]
    if (io_status == 'Y') or (sql_status == 'Y'):
        ip = os.popen("/sbin/ifconfig|grep 'inet addr'|awk '{print $2}'").read()
        get_local_ip = ip[ip.find(':')+1:ip.find('n')]
        mail_warn("%s"%get_local_ip)

if __name__ == "__main__":
    main()
3月 08

linux下查看使用硬盘IO过高的进程

  服务器cpu使用率不高,load比较高,所以要查看一下IO。硬盘IO可以通过命令vmstat或iostat获得(也可以用yum 安装dstat获得),网络IO可以用iftop命令获取。但是不知道那个进程使用硬盘IO比较高,通过查找没有找到相关命令,只好自己写个脚本进行统计处理。
  本脚本在CentOS6下(kernel2.6以上)python2.6测试通过。
  直接运行脚本,默认情况下收集3秒钟数据,显示读写最高的前三个进程。如用参数可以使用命令“python fhip.py 4 5 3”,第一个数位每次收集读写数据的间隔秒数,第二个数是打印出读写最多的n个进程,第三个为运行脚本的次数。因为参数部分写的比较简单那,所以用参数必须3个全写。

#!/bin/python 
#-*- coding:utf-8 -*- 
# Filename:    find_high_io_process
# Revision:    1.0 
# Date:        2013-3-8 
# Author:      simonzhang 
# web:         www.simonzhang.net 
# Email:       simon-zzm@163.com 
### END INIT INFO
import os
import re
import sys
import time
from string import strip

####
sys_proc_path = '/proc/'
re_find_process_number = '^\d+$'

####
# 通过/proc/$pid/io获取读写信息
####
def collect_info():
    _tmp = {}
    re_find_process_dir = re.compile(re_find_process_number)
    for i in os.listdir(sys_proc_path):
        if re_find_process_dir.search(i):
            # 获得进程名
            process_name = open("%s%s/stat" % (sys_proc_path, i), "rb").read().split(" ")[1]
            # 读取io信息
            rw_io = open("%s%s/io" % (sys_proc_path, i), "rb").readlines()
            for _info in rw_io:
                cut_info = strip(_info).split(':')
                if strip(cut_info[0]) == "read_bytes":
                    read_io = int(strip(cut_info[1]))
                if strip(cut_info[0]) == "write_bytes":
                    write_io = int(strip(cut_info[1]))
            _tmp[i] = {"name":process_name, "read_bytes":read_io, "write_bytes":write_io}
    return _tmp


def main(_sleep_time, _list_num):
    _sort_read_dict = {}
    _sort_write_dict = {}
    # 获取系统读写数据
    process_info_list_frist = collect_info()
    time.sleep(_sleep_time)
    process_info_list_second = collect_info()
    # 将读数据和写数据进行分组,写入两个字典中
    for loop in process_info_list_second.keys():
        second_read_v = process_info_list_second[loop]["read_bytes"]
        second_write_v = process_info_list_second[loop]["write_bytes"]
        try:
            frist_read_v = process_info_list_frist[loop]["read_bytes"]
        except:
            frist_read_v = 0
        try:
            frist_write_v = process_info_list_frist[loop]["write_bytes"]
        except:
            frist_write_v = 0
        # 计算第二次获得数据域第一次获得数据的差
        _sort_read_dict[loop] = second_read_v - frist_read_v
        _sort_write_dict[loop] = second_write_v - frist_write_v
    # 将读写数据进行排序
    sort_read_dict = sorted(_sort_read_dict.items(),key=lambda _sort_read_dict:_sort_read_dict[1],reverse=True)
    sort_write_dict = sorted(_sort_write_dict.items(),key=lambda _sort_write_dict:_sort_write_dict[1],reverse=True)
    # 打印统计结果
    print "pid     process     read(bytes) pid     process     write(btyes)"
    for _num in range(_list_num):
        read_pid = sort_read_dict[_num][0]
        write_pid = sort_write_dict[_num][0]
        res = "%s" % read_pid
        res += " " * (8 - len(read_pid)) + process_info_list_second[read_pid]["name"]
        res += " " * (12 - len(process_info_list_second[read_pid]["name"])) + "%s" % sort_read_dict[_num][1]
        res += " " * (12 - len("%s" % sort_read_dict[_num][1])) + write_pid
        res += " " * (8 - len(write_pid)) + process_info_list_second[write_pid]["name"]
        res += " " * (12 - len("%s" % process_info_list_second[write_pid]["name"])) + "%s" % sort_write_dict[_num][1]
        print res
    print "\n" * 1


if __name__ == '__main__':
    try:
        _sleep_time = sys.argv[1]
    except:
        _sleep_time = 3
    try:
        _num = sys.argv[2]
    except:
        _num = 3
    try:
        loop = sys.argv[3]
    except:
        loop = 1
    for i in range(int(loop)):
        main(int(_sleep_time), int(_num))

linux查找IO高的进程的源码