Tomcat企业级应用和高级实现
session会话保持方法:
(1) session sticky:source_ip(nginx: ip_hash、haproxy: source、lvs: sh)cookie(nginx:hash、haproxy: cookie)即在代理调度层做session
(2) session cluster:delta session manager
(3) session server:redis(store), memcached(cache)
Tomcat Cluster(session)
(1) session sticky
(2) session cluster tomcat delta manager
(3) session server memcached
Tomcat Cluster
(1) httpd + tomcat cluster
httpd: mod_proxy, mod_proxy_http, mod_proxy_balancer
tomcat cluster:http connector
(2) httpd + tomcat cluster
httpd: mod_proxy, mod_proxy_ajp, mod_proxy_balancer
tomcat cluster:ajp connector
(3) httpd + tomcat cluster
httpd: mod_jk
tomcat cluster:ajp connector
(4) nginx + tomcat cluster
示例程序:mkdir /usr/share/tomcat/webapp/myapp/{WEB-INF} -pv
vim /usr/share/tomcat/webapp/myapp/index.jsp
演示效果,在TomcatA上某context中(如/test),提供如下页面
<%@ page language="java" %>
<html>
<head><title>TomcatA</title></head>
<body>
<h1><font color="red">TomcatA.heiye.com</font></h1>
<table align="centre" border="1">
<tr>
<td>Session ID</td>
<% session.setAttribute("heiye.com","heiye.com"); %>
<td><%= session.getId() %></td>
</tr>
<tr>
<td>Created on</td>
<td><%= session.getCreationTime() %></td>
</tr>
</table>
</body>
</html>
演示效果,在TomcatB上某context中(如/test),提供如下页面
<%@ page language="java" %>
<html>
<head><title>TomcatB</title></head>
<body>
<h1><font color="blue">TomcatB.heiye.com</font></h1>
<table align="centre" border="1">
<tr>
<td>Session ID</td>
<% session.setAttribute("heiye.com","heiye.com"); %>
<td><%= session.getId() %></td>
</tr>
<tr>
<td>Created on</td>
<td><%= session.getCreationTime() %></td>
</tr>
</table>
</body>
</html>
第一种方法的实现:
<proxy balancer://tcsrvs>
BalancerMember http://172.18.64.107:8080 loadfactor 2 status=D
BalancerMember http://172.18.64.7:8080 loadfactor 1
ProxySet lbmethod=byrequests (bybusiness 、bytraffic)
</Proxy>
<VirtualHost *:80>
ServerName lb.heiye.com
ProxyVia On
ProxyRequests Off
ProxyPreserveHost On
<Proxy *>
Require all granted
</Proxy>
ProxyPass / balancer://tcsrvs/
ProxyPassReverse / balancer://tcsrvs/
<Location />
Require all granted
</Location>
</VirtualHost>
#启用管理接口:
#<Location /balancer-manager>
#SetHandler balancer-manager
#ProxyPass !
#Require all granted (真实生产环境必须作访问控制!)
#</Location>
F5刷新后测试,并进入balancer-manager管理页面,可直接对主机状态管理
会话粘性的实现方法:
Header add Set-Cookie "ROUTEID=.%{BALANCER_WORKER_ROUTE}e; path=/" env=BALANCER_ROUTE_CHANGED
<proxy balancer://tcsrvs>
BalancerMember http://172.18.64.107:8080 route=TomcatA loadfactor=1
BalancerMember http://172.18.64.7:8080 route=TomcatB loadfactor=2
ProxySet lbmethod=byrequests
ProxySet stickysession=ROUTEID
</Proxy>
<VirtualHost *:80>
ServerName lb.heiye.com
ProxyVia On
roxyRequests Off
ProxyPreserveHost On
<Proxy *>
Require all granted
</Proxy>
ProxyPass / balancer://tcsrvs/
ProxyPassReverse / balancer://tcsrvs/
<Location />
Require all granted
</Location>
</VirtualHost>
第二种方式:
<proxy balancer://tcsrvs>
BalancerMember jsp://172.18.64.107:8080 loadfactor 2 status=D
BalancerMember jsp://172.18.64.7:8080 loadfactor 1
ProxySet lbmethod=byrequests (bybusiness 、bytraffic)
</Proxy>
<VirtualHost *:80>
ServerName lb.heiye.com
ProxyVia On
ProxyRequests Off
ProxyPreserveHost On
<Proxy *>
Require all granted
</Proxy>
ProxyPass / balancer://tcsrvs/
ProxyPassReverse / balancer://tcsrvs/
<Location />
Require all granted
</Location>
</VirtualHost>
#启用管理接口:
#<Location /balancer-manager>
#SetHandler balancer-manager
#ProxyPass !
#Require all granted (真实生产环境必须作访问控制!)
#</Location>
第三种方式实现:nginx vim /etc/nginx/nginx.conf
upstream heiye {
server 172.18.64.107:8080;
server 172.18.64.7:8080;
}
# Load modular configuration files from the /etc/nginx/conf.d directory.
# See http://nginx.org/en/docs/ngx_core_module.html#include
# for more information.
include /etc/nginx/conf.d/*.conf;
server {
listen 80 default_server;
listen [::]:80 default_server;
server_name _;
index index.jsp index.html ;
root /usr/share/tomcat/webapps/ROOT/;
# Load configuration files for the default server block.
include /etc/nginx/default.d/*.conf;
location / {
proxy_pass http://heiye;
}
保持会话的方式参考前一种方式。
Tomcat Session Replication Cluster:
(1) 配置启用集群,将下列配置放置于<engine>或<host>中;
<Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster" channelSendOptions="8">
<Manager className="org.apache.catalina.ha.session.DeltaManager" expireSessionsOnShutdown="false" notifyListenersOnReplication="true"/> <Channel className="org.apache.catalina.tribes.group.GroupChannel"> <Membership className="org.apache.catalina.tribes.membership.McastService" address="228.0.0.4" port="45564" frequency="500" dropTime="3000"/> <Receiver className="org.apache.catalina.tribes.transport.nio.NioReceiver" address="auto" port="4000" autoBind="100" selectorTimeout="5000" maxThreads="6"/>
<Sender className="org.apache.catalina.tribes.transport.ReplicationTransmitter"> <Transport className="org.apache.catalina.tribes.transport.nio.PooledParallelSender"/> </Sender> <Interceptor className="org.apache.catalina.tribes.group.interceptors.TcpFailureDetector"/> <Interceptor className="org.apache.catalina.tribes.group.interceptors.MessageDispatch15Interceptor"/> </Channel> <Valve className="org.apache.catalina.ha.tcp.ReplicationValve" filter=""/> <Valve className="org.apache.catalina.ha.session.JvmRouteBinderValve"/> <Deployer className="org.apache.catalina.ha.deploy.FarmWarDeployer" tempDir="/tmp/war-temp/" deployDir="/tmp/war-deploy/" watchDir="/tmp/war-listen/" watchEnabled="false"/> <ClusterListener className="org.apache.catalina.ha.session.JvmRouteSessionIDBinderListener"/> <ClusterListener className="org.apache.catalina.ha.session.ClusterSessionListener"/> </Cluster>
确保Engine的jvmRoute属性配置正确。
(2) 配置webapps
编辑WEB-INF/web.xml,添加<distributable/>元素;
注意:CentOS 7上的tomcat自带的文档中的配置示例有语法错误;
<ClusterListener className="org.apache.catalina.ha.session.JvmRouteSessionIDBinderListener"/>
<ClusterListener className="org.apache.catalina.ha.session.ClusterSessionListener"/>
绑定的地址为auto时,会自动解析本地主机名,并解析得出的IP地址作为使用的地址;
Tomcat的常用优化配置:
(1) 内存空间:
/etc/sysconfig/tomcat
JAVA_OPTS="-server -Xms32g -Xmx32g -XX:NewSize= -XX:MaxNewSize= -XX:PermSize= -XX:MaxPermSize="
-server:服务器模型
-Xms:堆内存初始化大小;
-Xmx:堆内存空间上限;
-XX:NewSize=:新生代空间初始化大小;
-XX:MaxNewSize=:新生代空间最大值;
-XX:PermSize=:持久代空间初始化大小;
-XX:MaxPermSize=:持久代空间最大值;
(2) 线程池设置:
<Connector port="8080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" />
常用属性:
maxThreads:最大线程数;最大并发连接数;
minSpareThreads:最小空闲线程数;
maxSpareThreads:最大空闲线程数;
acceptCount:等待队列的最大长度;
URIEncoding:URI地址编码格式,建议使用UTF-8;
enableLookups:是否启用dns解析,建议禁用;
compression:是否启用传输压缩机制,建议“on";
compressionMinSize:启用压缩传输的数据流最小值,单位是字节;
compressableMimeType:定义启用压缩功能的MIME类型;
text/html, text/xml, text/css, text/javascript
(3) 禁用8005端口;
<Server port="-1" shutdown="SHUTDOWN">
(4) 隐藏版本信息:
<Connector port="8080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" />
Server="SOME STRING"
Tomcat Session Server (memcached)
https://github.com/magro/memcached-session-manager
支持的session server类型:
memcached:
couchbase:
redis:
示例方案:
Tomcat7:
memcached
javolution
JVM常用的分析工具:
jps:用来查看运行的所有jvm进程;
jinfo:查看进程的运行环境参数,主要是jvm命令行参数;
jstat:对jvm应用程序的资源和性能进行实时监控;
jstack:查看所有线程的运行状态;
jmap:查看jvm占用物理内存的状态;
jconsole:
jvisualvm:
jps:Java virutal machine Process Status tool,
jps [-q] [-mlvV] [<hostid>]
-q:静默模式;
-v:显示传递给jvm的命令行参数;
-m:输出传入main方法的参数;
-l:输出main类或jar完全限定名称;
-V:显示通过flag文件传递给jvm的参数;
[<hostid>]:主机id,默认为localhost;
jinfo:输出给定的java进程的所有配置信息;
jinfo [option] <pid>
-flags:to print VM flags
-sysprops:to print Java system properties
-flag <name>:to print the value of the named VM flag
jstack:查看指定的java进程的线程栈的相关信息;
jstack [-l] <pid>
jstack -F [-m] [-l] <pid>
-l:long listings,会显示额外的锁信息,因此,发生死锁时常用此选项;
-m:混合模式,既输出java堆栈信息,也输出C/C++堆栈信息;
-F:当使用“jstack -l PID"无响应,可以使用-F强制输出信息;
jstat:输出指定的java进程的统计信息
jstat -help|-options
jstat -<option> [-t] [-h<lines>] <vmid> [<interval> [<count>]]
# jstat -options
-class:class loader
-compiler:JIT
-gc:gc
-gccapacity:统计堆中各代的容量
-gccause:
-gcmetacapacity
-gcnew:新生代
-gcnewcapacity
-gcold:老年代
-gcoldcapacity
-gcutil
-printcompilation
[<interval> [<count>]]
interval:时间间隔,单位是毫秒;
count:显示的次数;
-gc:
YGC:新生代的垃圾回收次数;
YGCT:新生代垃圾回收消耗的时长;
FGC:Full GC的次数;
FGCT:Full GC消耗的时长;
GCT:GC消耗的总时长;
图形工具:
jconsole
jvisualvm
jmap:Memory Map, 用于查看堆内存的使用状态;
jhat:Java Heap Analysis Tool
jmap [option] <pid>
查看堆空间的详细信息:
jmap -heap <pid>
查看堆内存中的对象的数目:
jmap -histo[:live] <pid>
live:只统计活动对象;
保存堆内存数据至文件中,而后使用jvisualvm或jhat进行查看:
jmap -dump:<dump-options> <pid>
dump-options:
live dump only live objects; if not specified, all objects in the heap are dumped.
format=b binary format
file=<file> dump heap to <file>
了解何为full gc,如何应对