Tomcat

HTTP/1.0, send a request, create a connection, get a Web resource, and disconnect. HTTP/1.1, send a request, create a connection, get multiple Web resources, maintain the connection.

HTTP

request

The response

tomcat

The directory structure

• Bin: script directory startup script: startup.bat Stop script: shutdown.bat
• Conf: Configuration file directory (config /configuration) Core configuration file: server. XML User permission configuration file: tomcat-users. XML Default configuration file for all Web projects: web.xml
• Lib: Dependency libraries, jar packages used in Tomcat and Web projects
• Logs: log file localhost_access_logTXT Tomcat Records user access information, starRepresents time. For example: localhost_access_log. 2016-02-28. TXT
• Temp: indicates a temporary file directory. Contents in the folder can be deleted at will.
• Webapps: Directories where WEB projects are published by default.
• Work: Tomcat handles the working directory and session passivation files for the JSPS

Directory structure of Web applications

WEB. XML file (WEB configuration)Copy the code

Tomcat optimization

There are three operating modes of Tomcat:

• Bio Bio (Blocking I/O), as the name implies, means that Tomcat uses traditional Java I/O operations (the java.io package and its subpackages). Tomcat runs in BIO mode by default. Unfortunately, in general, BIO mode is the least performing of the three running modes. You can check the current status of the server using Tomcat Manager.

• Nio is a new way of doing I/O operations (that is, the java.niO package and its subpackages) provided with Java SE 1.4 and later. Java NIO is a buffer-based Java API that provides non-blocking I/O operations, so NIO is also known as an acronym for non-blocking I/O. It has better concurrency performance than traditional I/O operations (BIO).

• Apr (Apache Portable Runtime/Apache Portable Runtime) is a support library for the Apache HTTP server. You can think of it simply as Tomcat calls the Apache HTTP server’s core dynamic link library as JNI to handle file reads or network transfers, greatly improving Tomcat’s performance for static files. Tomcat APR is also the preferred mode for running highly concurrent applications on Tomcat.

1. Enable the NIO mode

Modify server. The Connector in the XML node, and modify the protocol for org. Apache. Coyote. Http11. Http11NioProtocol

<Connector port="8080" protocal="org.apache.coyote.http11.Http11NioProtocol" 
  connectionTimeout="20000" redirectPort="8443"/>
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2. Enable a thread pool

<! -- <Executor name="tomcatThreadPool" namePrefix="catalina-exec-"
        maxThreads="150" minSpareThreads="4"/>
    -->
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Open thread pools in server.xml and configure them for use in Connector

<! -- <Connector executor="tomcatThreadPool"
               port="8080" protocol="HTTP / 1.1"
               connectionTimeout="20000"
               redirectPort="8443" />
    -->
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• Parameters that

– Best Practices

<Executer name="tomcatThread Pool" namePrefix="catalina-exec-" 
maxThreads="800" minSpareThreads="100" maxQueueSize="100" prestartminSpareThreads="true"/>
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3. Connector

Connector is the gateway for Tomcat to receive requests. Each Connector has its own listening port. There are two types of Connector: HTTP Connector and AJPConnector

• General properties

• Standards implementation

• Disable AJP connectors

AJP (Apache JServerProtocol) AJPv13 protocol is package-oriented. The WEB server and Servlet container interact over a TCP connection; To save on costly SOCKET creation, the WEB server tries to maintain a permanent TCP connection to the servlet container and reuse the connection over multiple request and response cycles.

We generally use the Nginx+ Tomcat architecture, so we don’t need the AJP protocol, so we disable the AJP connector.

<! --<Connector port="8009" protocol="AJP / 1.3" redictPort="8443" />-->
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• Best practices

<Connector executor="tomcatThreadPool" 
protocal="org.apache.coyote.http11.Http11NioProtocol" 
          port="8080" 
          connectionTimeout="20000"
          redirectPort="8443" 
          enableLookups="false"
          maxPostSize="10485760"
          URIEncoding="UTF-8"
          acceptCount="100"
          acceptorThreadCount="2"
          disableUploadTimeout="ture"
          maxConnections="10000"
          SSLEnabled="false"
			   />
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4. Optimization of JVM parameters

• Java stack

The Java stack is associated with each thread, and the JVM allocates stack space to each thread when it is created. It is mainly used to store local variables during thread execution, method return values, and method call context. Stack space is freed as the thread terminates.

• The Java heap

In Java, the heap is an area of memory shared by all threads. The heap is used to hold various Java objects, such as arrays, thread objects, and so on.

Set appropriate JVM parameter optimizations, note the JDK version