存储+调优：存储-memcached
什么是memcached?
高性能的分布式内存缓存服务器。通过缓存数据库的查询结果，减少数据库访问次数，以提高动态Web应用的速度、提高可扩展性。
在memcached中存什么？
尽快被保存
访问频率高
1.数据保存方式 chunk
2.数据有效期
3.数据过期慵懒检查
4.数据的存取 set get
5。通过应用程序访问memcache
数据存储方式
chunk
数据过期方式
• Lazy Expiration
memcached内部不会监视记录是否过期，而是在get时查看记录的时间戳，检查记录是否过期。这种技术被称为lazy（惰性）expiration。因此，memcached不会在过期监视上耗费CPU时间。
• LRU
memcached会优先使用已超时的记录的空间，但即使如此，也会发生追加新记录时空间不足的情况，此时就要使用名为 Least Recently Used（LRU）机制来分配空间。顾名思义，这是删除“最近最少使用”的记录的机制。因此，当memcached的内存空间不足时（无法从slab class 获取到新的空间时），就从最近未被使用的记录中搜索，并将其空间分配给新的记录。从缓存的实用角度来看，该模型十分理想。
[root@localhost tmp]# tar xf libevent-2.0.15-stable.tar.gz
[root@localhost tmp]# cd libevent-2.0.15-stable
[root@localhost libevent-2.0.15-stable]# ./configure && make && make install
[root@localhost tmp]# tar xf memcached-1.4.5.tar.gz
[root@localhost tmp]# cd memcached-1.4.5
[root@localhost memcached-1.4.5]# ./configure && make && make install
[root@localhost memcached-1.4.5]# ./memcached -h
[root@localhost memcached-1.4.5]# ./memcached -p 11211 -l 172.16.1.6 -u root -m 64 -c 10 -vvv -f 1.2 -n 60
slab class 1: chunk size 96 perslab 10922
slab class 2: chunk size 120 perslab 8738
slab class 3: chunk size 144 perslab 7281
slab class 4: chunk size 176 perslab 5957
slab class 5: chunk size 216 perslab 4854
slab class 6: chunk size 264 perslab 3971
slab class 7: chunk size 320 perslab 3276
slab class 8: chunk size 384 perslab 2730
slab class 9: chunk size 464 perslab 2259
slab class 10: chunk size 560 perslab 1872
slab class 11: chunk size 672 perslab 1560
slab class 12: chunk size 808 perslab 1297
slab class 13: chunk size 976 perslab 1074
slab class 14: chunk size 1176 perslab 891
slab class 15: chunk size 1416 perslab 740
slab class 16: chunk size 1704 perslab 615
slab class 17: chunk size 2048 perslab 512
slab class 18: chunk size 2464 perslab 425
slab class 19: chunk size 2960 perslab 354
slab class 20: chunk size 3552 perslab 295
slab class 21: chunk size 4264 perslab 245
slab class 22: chunk size 5120 perslab 204
slab class 23: chunk size 6144 perslab 170
slab class 24: chunk size 7376 perslab 142
slab class 25: chunk size 8856 perslab 118
slab class 26: chunk size 10632 perslab 98
slab class 27: chunk size 12760 perslab 82
slab class 28: chunk size 15312 perslab 68
slab class 29: chunk size 18376 perslab 57
slab class 30: chunk size 22056 perslab 47
slab class 31: chunk size 26472 perslab 39
slab class 32: chunk size 31768 perslab 33
slab class 33: chunk size 38128 perslab 27
slab class 34: chunk size 45760 perslab 22
slab class 35: chunk size 54912 perslab 19
slab class 36: chunk size 65896 perslab 15
slab class 37: chunk size 79080 perslab 13
slab class 38: chunk size 94896 perslab 11
slab class 39: chunk size 113880 perslab 9
slab class 40: chunk size 136656 perslab 7
slab class 41: chunk size 163992 perslab 6
slab class 42: chunk size 196792 perslab 5
slab class 43: chunk size 236152 perslab 4
slab class 44: chunk size 283384 perslab 3
slab class 45: chunk size 340064 perslab 3
slab class 46: chunk size 408080 perslab 2
slab class 47: chunk size 489696 perslab 2
slab class 48: chunk size 587640 perslab 1
slab class 49: chunk size 705168 perslab 1
slab class 50: chunk size 846208 perslab 1
slab class 51: chunk size 1048576 perslab 1
<26 server listening (auto-negotiate)
<27 send buffer was 110592, now 268435456
<27 server listening (udp)
<27 server listening (udp)
<27 server listening (udp)
<27 server listening (udp)
[root@node1 ~]# telnet 172.16.1.6 11211
Trying 172.16.1.6...
Connected to 172.16.1.6 (172.16.1.6).
Escape character is '^]'.
<27 server listening (udp)
<27 server listening (udp)
<27 server listening (udp)
<27 server listening (udp)
<28 new auto-negotiating client connection
[root@node1 ~]# telnet 172.16.1.6 11211
Trying 172.16.1.6...
Connected to 172.16.1.6 (172.16.1.6).
Escape character is '^]'.
set nothing 0 180 10 ----- 0:标识 180：过期时间 10：多少字节
1234567890
STORED
get nothing
VALUE nothing 0 10
1234567890
END
[root@node1 ~]# yum install httpd php
[root@node1 ~]# rpm -ivh php-pecl-memcache-2.1.2-1.el5.rf.i386.rpm
[root@node1 ~]# cp test.php /var/www/html/
[root@node1 ~]# vim /var/www/html/test.php
<?php
$memcache = new Memcache;
$memcache->connect('172.16.1.6',11211) or die ("Could not connect");
$version = $memcache->getVersion();
echo "Server's version: ".$version."<br/>\n";
$tmp_object = new stdClass;
$tmp_object->str_attr = 'test';
$tmp_object->int_attr = 123;
$memcache->set('key', $tmp_object, false, 10) or die ("Failed to save data at the server");
echo "Store data in the cache (data will expire in 10 seconds)<br/>\n";
$get_result = $memcache->get('key');
echo "Data from the cache:<br/>\n";
var_dump($get_result);
?>
[root@node1 ~]# service httpd start
[root@localhost ~]# elinks --dump http://172.16.1.1/test.php
Server's version: 1.4.5
Store data in the cache (data will expire in 10 seconds)
Data from the cache:
object(stdClass)#3 (2) { ["str_attr"]=> string(4) "test" ["int_attr"]=>
int(123) }
apache + tomcat + memcached
apache 作为分发器
tomcat 提供web服务
mc 保证session同步
ip 192.168.1.106
apache:
yum install httpd httpd-devel gcc -y
ajp1.3:
tar zxvf tomcat-connectors-1.2.32-src.tar.gz -C /tmp
cat /tmp/tomcat-connectors-1.2.32-src/BUILD.txt
cd native
./configure --with-apxs=/usr/sbin/apxs
make && make install
cp ../conf/httpd-jk.conf /etc/httpd/conf.d/jk.conf
vim /etc/httpd/conf.d/jk.conf
JkMount /*.jsp wlb
JkMount /manager/* wlb
cp ../conf/workers.properties /etc/httpd/conf
vim /etc/httpd/conf/workers.properties
worker.list=wlb,jkstatus
worker.wlb.type=lb
worker.wlb.balance_workers=tomcat1,tomcat2
worker.tomcat1.type=ajp13
worker.tomcat1.host=192.168.1.111
worker.tomcat1.port=8009
worker.tomcat1.lbfactor=1
worker.tomcat2.type=ajp13
worker.tomcat2.host=192.168.1.112
worker.tomcat2.port=8009
worker.tomcat2.lbfactor=1
/etc/init.d/httpd restart
ip 192.168.1.111 192.168.1.112
jdk:
service httpd stop
chmod +x jdk-6u27-linux-i586.bin
./jdk-6u27-linux-i586.bin
mv jdk1.6.0_27/ /usr/local/jdk
vim /etc/bashrc
export JAVA_HOME=/usr/local/jdk
export JAVA_BIN=/usr/local/jdk/bin/
export PATH=$JAVA_HOME/bin:$PATH
export CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
export JAVA_HOME JAVA_BIN PATH CLASSPATH
source /etc/bashrc
java -version
mv apache-tomcat-6.0.32 /usr/local/tomcat
tomcat:
tar zxf apache-tomcat-6.0.32.tar.gz
mv apache-tomcat-6.0.32 /usr/local/tomcat
cd /usr/local/tomcat/bin
./startup.sh
cat >/usr/local/tomcat/webapps/ROOT/index.jsp <<EOF
<html>
<body bgcolor="red">
<center>
<%= request.getSession().getId() %>
<h1>Tomcat 1</h1>
</body>
</html>
 python2.7改为python3)
