使用死循环消耗CPU资源，如果服务器是有多颗CPU，可以选择消耗多少颗CPU的资源：
#! /bin/sh
# filename killcpu.sh
for i in `seq $1`
do
echo -ne "
i=0;
while true
do
i=i+1;
done" | /bin/sh &
pid_array[$i]=$! ;
done
for i in "${pid_array[@]}"; do
echo 'kill ' $i ';';
done
使用方法很简单，参数3表示消耗3颗CPU的资源，运行后，会有一堆 kill 命令，方便 kill 进程：
[root@test02 ~]# ./killcpu.sh 3
kill 30104 ;
kill 30106 ;
kill 30108 ;
[root@test02 ~]# top
top - 15:27:31 up 264 days, 23:39, 4 users, load average: 0.86, 0.25, 0.19
Tasks: 185 total, 5 running, 180 sleeping, 0 stopped, 0 zombie
Cpu0 : 100.0% us, 0.0% sy, 0.0% ni, 0.0% id, 0.0% wa, 0.0% hi, 0.0% si
Cpu1 : 0.0% us, 0.0% sy, 0.0% ni, 100.0% id, 0.0% wa, 0.0% hi, 0.0% si
Cpu2 : 100.0% us, 0.0% sy, 0.0% ni, 0.0% id, 0.0% wa, 0.0% hi, 0.0% si
Cpu3 : 100.0% us, 0.0% sy, 0.0% ni, 0.0% id, 0.0% wa, 0.0% hi, 0.0% si
Mem: 8165004k total, 8095880k used, 69124k free, 53672k buffers
Swap: 2031608k total, 103548k used, 1928060k free, 6801364k cached
使用suphp来执行php
1、yum安装环境
apache php 都是用Yum安装
# yum install httpd php php-cli
保证php有php-cgi，因为suphp需要php的执行模式为cgi/fastcgi
[vnp.unscnb.com:/root]#php -v
PHP 5.2.6 (cli) (built: May 5 2008 10:32:59)
Copyright (c) 1997-2008 The PHP Group
Zend Engine v2.2.0, Copyright (c) 1998-2008 Zend Technologies
[vnp.unscnb.com:/root]#php-cgi -v
PHP 5.2.6 (cgi-fcgi) (built: May 5 2008 10:29:53)
Copyright (c) 1997-2008 The PHP Group
Zend Engine v2.2.0, Copyright (c) 1998-2008 Zend Technologies
Suphp安装
# wgethttp://www.suphp.org/download/suphp-0.7.1.tar.gz
#tar zvxf suphp-0.7.1.tar.gz
#cd suphp-0.7.1
Suphp的编译参数有2种 主要是setid-mode的区别
1、测试模式，没有任何安全所言
#./configure --prefix=/usr/local/suphp \
--sysconfdir=/usr/local/suphp/etc \
--with-apache-user=apache \
--with-setid-mode=owner \
--with-apxs=/usr/sbin/apxs \
--with-apr=/usr/bin/apr-1-config
2、生产模式使用下面的配置
#./configure --prefix=/usr/local/suphp \
--sysconfdir=/usr/local/suphp/etc \
--with-apache-user=apache \
--with-setid-mode=paranoid
\
--with-apxs=/usr/sbin/apxs \
--with-apr=/usr/bin/apr-1-config
具体2者的区别 将在后面apache配置那里说明
# make
# make install
# mkdir/usr/local/suphp/etc
#cp doc/suphp.conf-example /usr/local/suphp/etc/suphp.conf
编辑suphp.conf
# vi/usr/local/suphp/etc/suphp.conf
###########----------------------------------
[global]
;日志文件的产生路径
logfile=/var/log/httpd/suphp.log
;日志级别"info", "warn", "error", "none".
loglevel=info
;User Apache is running as
webserver_user=apache
;Path all scripts have to be in
docroot=/
;Path to chroot() to before executing script
;chroot=/mychroot
;安全选项，根据自己需要开启
;allow_file_group_writeable=false
allow_file_group_writeable=true
allow_file_others_writeable=false
;allow_directory_group_writeable=false
allow_directory_group_writeable=true
allow_directory_others_writeable=false
;Check wheter script is within DOCUMENT_ROOT
check_vhost_docroot=true
;check_vhost_docroot=false
;Send minor error messages to browser
errors_to_browser=false
;PATH environment variable
env_path=/bin:/usr/bin
;Umask to set, specify in octal notation
umask=0077
;最小uid和最下gid是指web运行的用户和组必须大于等于这个数，否则由于安全员应无法运行，这个设置根据自己来设置，一般uid=500 gid=100
min_uid=1000
min_gid=1000
[handlers]
;必须执行cgi模式的php，这个很重要
;x-httpd-php="php:/usr/bin/php"
x-httpd-php="php:/usr/bin/php-cgi"
;Handler for CGI-scripts
x-suphp-cgi="execute:!self"
##################---------------------------------------
整合apache
注销所有原先php和apache的配置选项，包括模块
# vi /etc/httpd/conf.d/suphp.conf
####--------------
LoadModule suphp_module modules/mod_suphp.so
NameVirtualHost *:80
<VirtualHost *:80>
ServerName 127.0.0.1
DocumentRoot /var/www/svnadmin
DirectoryIndex index.php
#开启suphp引擎
suPHP_Engine on
#指定/var/www/svnadmin的运行用户和组
suPHP_UserGroup webtest1 suphp
#指定执行的扩展名
AddHandler x-httpd-php .php .php3 .php4 .php5
suPHP_AddHandler x-httpd-php
#指定php的配置文件
suPHP_ConfigPath /etc/php.ini
</VirtualHost>
###########-------------
需要注意的事项
1、假设apache设置的DocumentRoot "/var/www/html",那么/var/www的目录的所有者和组必须是root:root权限一般设置755
2、所有的虚拟主机web目录，必须放置在/var/www下，不能放置在apache设置的DocumentRoot目录下
3、假设我有一个/webserver/www/test的虚拟主机，此时/webserver/www的宿主和组必须是root:root
测试是否成功
编写index.php
<?
Phpinfo();
?>
打开web浏览发现
就表示成功
2、源码安装
suphp比suexec（就是原来dv3.0升php5的方法）要快一点；比suphp更快的还有suphp_mod_php；再快一些的是mpm-peruser，不过安装配置的麻烦程度也随之递增。
相比而言，suPHP速度还算可以接受（对于负载不是很大的站），配置方便，不用修改每个virtualhost的参数（就是$HOME/conf/vhost.conf），直接改apache的总conf就ok了，当然也比上面fastcgi方式下用event触发脚本来实现更加简洁。
ApacheSuexec
1、yum安装
#cd /etc/yum.repos.d/
#wgethttp://centos.karan.org/kbsingh-CentOS-Extras.repo
... and setgpgcheckto0andenabledto1in the[kbs-CentOS-Testing]section:
[...]
[kbs-CentOS-Testing]
name=CentOS.Karan.Org-EL$releasever - Testing
gpgcheck=0
gpgkey=http://centos.karan.org/RPM-GPG-KEY-karan.org.txt
enabled=1
baseurl=http://centos.karan.org/el$releasever/extras/testing/$basearch/RPMS/
#yum install httpd mod_fcgid php-cli
整合apache
注销所有原先php和apache的配置选项，包括模块
在php.ini的最后加上下面的语句
cgi.fix_pathinfo = 1
#groupadd web1
#useradd -s /bin/false -d /var/www/web1 -m -g web1 web1
#chmod 755 /var/www/web1
#mkdir -p /var/www/web1/web
#chown web1:web1 /var/www/web1/web
We will run PHP using suExec; suExec's document root is /var/www, as the following command shows:
# /usr/sbin/suexec -V
-D AP_DOC_ROOT="/var/www"
-D AP_GID_MIN=100
-D AP_HTTPD_USER="apache"
-D AP_LOG_EXEC="/var/log/httpd/suexec.log"
-D AP_SAFE_PATH="/usr/local/bin:/usr/bin:/bin"
-D AP_UID_MIN=500
-D AP_USERDIR_SUFFIX="public_html"
Therefore we cannot call the PHP binary (/usr/bin/php-cgi) directly because it is located outside suExec's document root. As suExec does not allow symlinks, the only way to solve the problem is to create a wrapper script for each web site in a subdirectory of /var/www; the wrapper script will then call the PHP binary /usr/bin/php-cgi. The wrapper script must be owned by the user and group of each web site, therefore we need one wrapper script for each web site. I'm going to create the wrapper scripts in subdirectories of /var/www/php-fcgi-scripts, e.g. /var/www/php-fcgi-scripts/web1
#mkdir -p /var/www/php-fcgi-scripts/web1
#vi /var/www/php-fcgi-scripts/web1/php-fcgi-starter
#!/bin/sh PHPRC=/etc/ export PHPRC export PHP_FCGI_MAX_REQUESTS=5000 export PHP_FCGI_CHILDREN=8 exec /usr/bin/php-cgi |
#chmod 755 /var/www/php-fcgi-scripts/web1/php-fcgi-starter
#chown -R web1:web1 /var/www/php-fcgi-scripts/web1
#vi /etc/httpd/conf.d/fcgid.conf
#######################--------------------------------
# This is the Apache server configuration file for providing FastCGI support
# through mod_fcgid
#
# Documentation is available at http://fastcgi.coremail.cn/doc.htm
LoadModule fcgid_module modules/mod_fcgid.so
# Use FastCGI to process .fcg .fcgi & .fpl scripts
# Don't do this if mod_fastcgi is present, as it will try to do the same thing
#<IfModule !mod_fastcgi.c>
# AddHandler fcgid-script fcg fcgi fpl
#</IfModule>
# Sane place to put sockets and shared memory file
SocketPath run/mod_fcgid
SharememPath run/mod_fcgid/fcgid_shm
IPCConnectTimeout 10
IPCCommTimeout 20
OutputBufferSize 0
MaxRequestsPerProcess 500
#AddHandler fcgid-script .fcgi .php
NameVirtualHost *:80
<VirtualHost *:80>
ServerName fcgi.test.com
DocumentRoot /var/www/fcgi
SuexecUserGroup webcgi fcgi
PHP_Fix_Pathinfo_Enable 1
AddHandler fcgid-script .php
<Directory /var/www/fcgi/>
Options +ExecCGI
AllowOverride All
FCGIWrapper /var/www/php-fcgi-scripts/web1/php-fcgi-starter .php
Order allow,deny
Allow from all
</Directory>
ServerSignature Off
</VirtualHost>
Q:Apache reports "SuexecUserGroup directive requires SUEXEC wrapper." warning during startup.
A:warning, 原因是错误的suEXEC权限设置。
查看 ： # ls -la /usr/sbin/suexec
应该为： -rwsr-xr-x 1 root root 12064 2008-04-17 01:15 /usr/sbin/suexec
主要是s权限即UID。如果权限和上面的不一样，修改：
# sudo chown root:root /usr/sbin/suexec
# sudo chmod 4755 /usr/sbin/suexec
本文转自centos.blog.chinaunix.net