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| <!DOCTYPE document [ |
| <!ENTITY project SYSTEM "project.xml"> |
| ]> |
| <document url="ajp.html"> |
| |
| &project; |
| |
| <properties> |
| <author email="yoavs@apache.org">Yoav Shapira</author> |
| <author email="arjaquith@mindspring.com">Andrew R. Jaquith</author> |
| <title>The AJP Connector</title> |
| </properties> |
| |
| <body> |
| |
| <section name="Table of Contents"> |
| <toc/> |
| </section> |
| |
| <section name="Introduction"> |
| |
| <p>The <strong>AJP Connector</strong> element represents a |
| <strong>Connector</strong> component that communicates with a web |
| connector via the <code>AJP</code> protocol. This is used for cases |
| where you wish to invisibly integrate Tomcat into an existing (or new) |
| Apache installation, and you want Apache to handle the static content |
| contained in the web application, and/or utilize Apache's SSL |
| processing.</p> |
| |
| <p>This connector supports load balancing when used in conjunction with |
| the <code>jvmRoute</code> attribute of the |
| <a href="engine.html">Engine</a>.</p> |
| |
| <p>The native connectors supported with this Tomcat release are:</p> |
| <ul> |
| <li>JK 1.2.x with any of the supported servers. See |
| <a href="http://tomcat.apache.org/connectors-doc/">the JK docs</a> |
| for details.</li> |
| <li>mod_proxy on Apache httpd 2.x (included by default in Apache HTTP |
| Server 2.2), with AJP enabled: see |
| <a href="http://httpd.apache.org/docs/2.2/mod/mod_proxy_ajp.html">the |
| httpd docs</a> for details.</li> |
| </ul> |
| |
| <p><b>Other native connectors supporting AJP may work, but are no longer |
| supported.</b></p> |
| |
| </section> |
| |
| |
| <section name="Attributes"> |
| |
| <subsection name="Common Attributes"> |
| |
| <p>All implementations of <strong>Connector</strong> |
| support the following attributes:</p> |
| |
| <attributes> |
| |
| <attribute name="ajpFlush" required="false"> |
| <p>A boolean value which can be used to enable or disable sending |
| AJP flush messages to the fronting proxy whenever an explicit |
| flush happens. The default value is <code>true</code>.<br/> |
| An AJP flush message is a SEND_BODY_CHUNK packet with no body content. |
| Proxy implementations like mod_jk or mod_proxy_ajp will flush the |
| data buffered in the web server to the client when they receive |
| such a packet. Setting this to <code>false</code> can reduce |
| AJP packet traffic but might delay sending packets to the client. |
| At the end of the response, AJP does always flush to the client.</p> |
| </attribute> |
| |
| <attribute name="allowTrace" required="false"> |
| <p>A boolean value which can be used to enable or disable the TRACE |
| HTTP method. If not specified, this attribute is set to false.</p> |
| </attribute> |
| |
| <attribute name="asyncTimeout" required="false"> |
| <p>The default timeout for asynchronous requests in milliseconds. If not |
| specified, this attribute is set to the Servlet specification default of |
| 30000 (30 seconds).</p> |
| </attribute> |
| |
| <attribute name="enableLookups" required="false"> |
| <p>Set to <code>true</code> if you want calls to |
| <code>request.getRemoteHost()</code> to perform DNS lookups in |
| order to return the actual host name of the remote client. Set |
| to <code>false</code> to skip the DNS lookup and return the IP |
| address in String form instead (thereby improving performance). |
| By default, DNS lookups are disabled.</p> |
| </attribute> |
| |
| <attribute name="maxHeaderCount" required="false"> |
| <p>The maximum number of headers in a request that are allowed by the |
| container. A request that contains more headers than the specified limit |
| will be rejected. A value of less than 0 means no limit. |
| If not specified, a default of 100 is used.</p> |
| </attribute> |
| |
| <attribute name="maxParameterCount" required="false"> |
| <p>The maximum number of parameter and value pairs (GET plus POST) which |
| will be automatically parsed by the container. Parameter and value pairs |
| beyond this limit will be ignored. A value of less than 0 means no limit. |
| If not specified, a default of 10000 is used. Note that |
| <code>FailedRequestFilter</code> <a href="filter.html">filter</a> can be |
| used to reject requests that hit the limit.</p> |
| </attribute> |
| |
| <attribute name="maxPostSize" required="false"> |
| <p>The maximum size in bytes of the POST which will be handled by |
| the container FORM URL parameter parsing. The limit can be disabled by |
| setting this attribute to a value less than zero. If not specified, this |
| attribute is set to 2097152 (2 megabytes). Note that the |
| <a href="filter.html#Failed_Request_Filter"><code>FailedRequestFilter</code></a> |
| can be used to reject requests that exceed this limit.</p> |
| </attribute> |
| |
| <attribute name="maxSavePostSize" required="false"> |
| <p>The maximum size in bytes of the POST which will be saved/buffered by |
| the container during FORM or CLIENT-CERT authentication. For both types |
| of authentication, the POST will be saved/buffered before the user is |
| authenticated. For CLIENT-CERT authentication, the POST is buffered for |
| the duration of the SSL handshake and the buffer emptied when the request |
| is processed. For FORM authentication the POST is saved whilst the user |
| is re-directed to the login form and is retained until the user |
| successfully authenticates or the session associated with the |
| authentication request expires. The limit can be disabled by setting this |
| attribute to -1. Setting the attribute to zero will disable the saving of |
| POST data during authentication. If not specified, this attribute is set |
| to 4096 (4 kilobytes).</p> |
| </attribute> |
| |
| <attribute name="parseBodyMethods" required="false"> |
| <p>A comma-separated list of HTTP methods for which request |
| bodies will be parsed for request parameters identically |
| to POST. This is useful in RESTful applications that want to |
| support POST-style semantics for PUT requests. |
| Note that any setting other than <code>POST</code> causes Tomcat |
| to behave in a way that goes against the intent of the servlet |
| specification. |
| The HTTP method TRACE is specifically forbidden here in accordance |
| with the HTTP specification. |
| The default is <code>POST</code></p> |
| </attribute> |
| |
| <attribute name="port" required="true"> |
| <p>The TCP port number on which this <strong>Connector</strong> |
| will create a server socket and await incoming connections. Your |
| operating system will allow only one server application to listen |
| to a particular port number on a particular IP address. If the special |
| value of 0 (zero) is used, then Tomcat will select a free port at random |
| to use for this connector. This is typically only useful in embedded and |
| testing applications.</p> |
| </attribute> |
| |
| <attribute name="protocol" required="false"> |
| <p>Sets the protocol to handle incoming traffic. To configure an AJP |
| connector this must be specified. If no value for protocol is provided, |
| an <a href="http.html">HTTP connector</a> rather than an AJP connector |
| will be configured.<br/> |
| The standard protocol value for an AJP connector is <code>AJP/1.3</code> |
| which uses an auto-switching mechanism to select either a Java NIO based |
| connector or an APR/native based connector. If the |
| <code>PATH</code> (Windows) or <code>LD_LIBRARY_PATH</code> (on most unix |
| systems) environment variables contain the Tomcat native library, the |
| native/APR connector will be used. If the native library cannot be |
| found, the Java NIO based connector will be used.<br/> |
| To use an explicit protocol rather than rely on the auto-switching |
| mechanism described above, the following values may be used:<br/> |
| <code>org.apache.coyote.ajp.AjpProtocol</code> |
| - blocking Java connector<br/> |
| <code>org.apache.coyote.ajp.AjpNioProtocol</code> |
| - non blocking Java NIO connector.<br/> |
| <code>org.apache.coyote.ajp.AjpNio2Protocol</code> |
| - non blocking Java NIO2 connector.<br/> |
| <code>org.apache.coyote.ajp.AjpAprProtocol</code> |
| - the APR/native connector.<br/> |
| Custom implementations may also be used.<br/> |
| Take a look at our <a href="#Connector_Comparison">Connector |
| Comparison</a> chart. |
| </p> |
| </attribute> |
| |
| <attribute name="proxyName" required="false"> |
| <p>If this <strong>Connector</strong> is being used in a proxy |
| configuration, configure this attribute to specify the server name |
| to be returned for calls to <code>request.getServerName()</code>. |
| See <a href="#Proxy_Support">Proxy Support</a> for more |
| information.</p> |
| </attribute> |
| |
| <attribute name="proxyPort" required="false"> |
| <p>If this <strong>Connector</strong> is being used in a proxy |
| configuration, configure this attribute to specify the server port |
| to be returned for calls to <code>request.getServerPort()</code>. |
| See <a href="#Proxy_Support">Proxy Support</a> for more |
| information.</p> |
| </attribute> |
| |
| <attribute name="redirectPort" required="false"> |
| <p>If this <strong>Connector</strong> is supporting non-SSL |
| requests, and a request is received for which a matching |
| <code><security-constraint></code> requires SSL transport, |
| Catalina will automatically redirect the request to the port |
| number specified here.</p> |
| </attribute> |
| |
| <attribute name="scheme" required="false"> |
| <p>Set this attribute to the name of the protocol you wish to have |
| returned by calls to <code>request.getScheme()</code>. For |
| example, you would set this attribute to "<code>https</code>" |
| for an SSL Connector. The default value is "<code>http</code>". |
| </p> |
| </attribute> |
| |
| <attribute name="secure" required="false"> |
| <p>Set this attribute to <code>true</code> if you wish to have |
| calls to <code>request.isSecure()</code> to return <code>true</code> |
| for requests received by this Connector. You would want this on an |
| SSL Connector or a non SSL connector that is receiving data from a |
| SSL accelerator, like a crypto card, a SSL appliance or even a webserver. |
| The default value is <code>false</code>.</p> |
| </attribute> |
| |
| <attribute name="URIEncoding" required="false"> |
| <p>This specifies the character encoding used to decode the URI bytes, |
| after %xx decoding the URL. If not specified, UTF-8 will be used unless |
| the <code>org.apache.catalina.STRICT_SERVLET_COMPLIANCE</code> |
| <a href="systemprops.html">system property</a> is set to <code>true</code> |
| in which case ISO-8859-1 will be used.</p> |
| </attribute> |
| |
| <attribute name="useBodyEncodingForURI" required="false"> |
| <p>This specifies if the encoding specified in contentType should be used |
| for URI query parameters, instead of using the URIEncoding. This |
| setting is present for compatibility with Tomcat 4.1.x, where the |
| encoding specified in the contentType, or explicitly set using |
| Request.setCharacterEncoding method was also used for the parameters from |
| the URL. The default value is <code>false</code>. |
| </p> |
| <p><em>Notes:</em> See notes on this attribute in |
| <a href="http.html">HTTP Connector</a> documentation.</p> |
| </attribute> |
| |
| <attribute name="useIPVHosts" required="false"> |
| <p>Set this attribute to <code>true</code> to cause Tomcat to use |
| the IP address passed by the native web server to determine the Host |
| to send the request to. The default value is <code>false</code>.</p> |
| </attribute> |
| |
| <attribute name="xpoweredBy" required="false"> |
| <p>Set this attribute to <code>true</code> to cause Tomcat to advertise |
| support for the Servlet specification using the header recommended in the |
| specification. The default value is <code>false</code>.</p> |
| </attribute> |
| |
| </attributes> |
| |
| </subsection> |
| |
| <subsection name="Standard Implementations"> |
| |
| <p>To use AJP, you must specify the protocol attribute (see above).</p> |
| |
| <p>The standard AJP connectors (BIO, NIO, NIO2 and APR/native) all support |
| the following attributes in addition to the common Connector attributes |
| listed above.</p> |
| |
| <attributes> |
| |
| <attribute name="acceptCount" required="false"> |
| <p>The maximum queue length for incoming connection requests when |
| all possible request processing threads are in use. Any requests |
| received when the queue is full will be refused. The default |
| value is 100.</p> |
| </attribute> |
| |
| <attribute name="acceptorThreadCount" required="false"> |
| <p>The number of threads to be used to accept connections. Increase this |
| value on a multi CPU machine, although you would never really need more |
| than <code>2</code>. Also, with a lot of non keep alive connections, you |
| might want to increase this value as well. Default value is |
| <code>1</code>.</p> |
| </attribute> |
| |
| <attribute name="acceptorThreadPriority" required="false"> |
| <p>The priority of the acceptor threads. The threads used to accept |
| new connections. The default value is <code>5</code> (the value of the |
| <code>java.lang.Thread.NORM_PRIORITY</code> constant). See the JavaDoc |
| for the <code>java.lang.Thread</code> class for more details on what |
| this priority means.</p> |
| </attribute> |
| |
| <attribute name="address" required="false"> |
| <p>For servers with more than one IP address, this attribute |
| specifies which address will be used for listening on the specified |
| port. By default, this port will be used on all IP addresses |
| associated with the server. A value of <code>127.0.0.1</code> |
| indicates that the Connector will only listen on the loopback |
| interface.</p> |
| </attribute> |
| |
| <attribute name="bindOnInit" required="false"> |
| <p>Controls when the socket used by the connector is bound. By default it |
| is bound when the connector is initiated and unbound when the connector is |
| destroyed. If set to <code>false</code>, the socket will be bound when the |
| connector is started and unbound when it is stopped.</p> |
| </attribute> |
| |
| <attribute name="clientCertProvider" required="false"> |
| <p>When client certificate information is presented in a form other than |
| instances of <code>java.security.cert.X509Certificate</code> it needs to |
| be converted before it can be used and this property controls which JSSE |
| provider is used to perform the conversion. For example it is used with |
| the AJP connectors, the <a href="http.html">HTTP APR connector</a> and |
| with the <a href="valve.html#SSL_Authenticator_Valve"> |
| org.apache.catalina.valves.SSLValve</a>.If not specified, the default |
| provider will be used.</p> |
| </attribute> |
| |
| <attribute name="connectionLinger" required="false"> |
| <p>The number of seconds during which the sockets used by this |
| <strong>Connector</strong> will linger when they are closed. The default |
| value is <code>-1</code> which disables socket linger.</p> |
| </attribute> |
| |
| <attribute name="connectionTimeout" required="false"> |
| <p>The number of milliseconds this <strong>Connector</strong> will wait, |
| after accepting a connection, for the request URI line to be |
| presented. The default value for AJP protocol connectors |
| is <code>-1</code> (i.e. infinite).</p> |
| </attribute> |
| |
| <attribute name="executor" required="false"> |
| <p>A reference to the name in an <a href="executor.html">Executor</a> |
| element. If this attribute is set, and the named executor exists, the |
| connector will use the executor, and all the other thread attributes will |
| be ignored. Note that if a shared executor is not specified for a |
| connector then the connector will use a private, internal executor to |
| provide the thread pool.</p> |
| </attribute> |
| |
| <attribute name="executorTerminationTimeoutMillis" required="false"> |
| <p>The time that the private internal executor will wait for request |
| processing threads to terminate before continuing with the process of |
| stopping the connector. If not set, the default is <code>0</code> (zero) |
| for the BIO connector and <code>5000</code> (5 seconds) for the NIO, NIO2 |
| and APR/native connectors.</p> |
| </attribute> |
| |
| <attribute name="keepAliveTimeout" required="false"> |
| <p>The number of milliseconds this <strong>Connector</strong> will wait for |
| another AJP request before closing the connection. |
| The default value is to use the value that has been set for the |
| connectionTimeout attribute.</p> |
| </attribute> |
| |
| <attribute name="maxConnections" required="false"> |
| <p>The maximum number of connections that the server will accept and |
| process at any given time. When this number has been reached, the server |
| will accept, but not process, one further connection. This additional |
| connection be blocked until the number of connections being processed |
| falls below <strong>maxConnections</strong> at which point the server will |
| start accepting and processing new connections again. Note that once the |
| limit has been reached, the operating system may still accept connections |
| based on the <code>acceptCount</code> setting. The default value varies by |
| connector type. For BIO the default is the value of |
| <strong>maxThreads</strong> unless an <a href="executor.html">Executor</a> |
| is used in which case the default will be the value of maxThreads from the |
| executor. For NIO and NIO2 the default is <code>10000</code>. |
| For APR/native, the default is <code>8192</code>.</p> |
| <p>Note that for APR/native on Windows, the configured value will be |
| reduced to the highest multiple of 1024 that is less than or equal to |
| maxConnections. This is done for performance reasons.<br/> |
| If set to a value of -1, the maxConnections feature is disabled |
| and connections are not counted.</p> |
| </attribute> |
| |
| <attribute name="maxCookieCount" required="false"> |
| <p>The maximum number of cookies that are permitted for a request. A value |
| of less than zero means no limit. If not specified, a default value of 200 |
| will be used.</p> |
| </attribute> |
| |
| <attribute name="maxThreads" required="false"> |
| <p>The maximum number of request processing threads to be created |
| by this <strong>Connector</strong>, which therefore determines the |
| maximum number of simultaneous requests that can be handled. If |
| not specified, this attribute is set to 200. If an executor is associated |
| with this connector, this attribute is ignored as the connector will |
| execute tasks using the executor rather than an internal thread pool. Note |
| that if an executor is configured any value set for this attribute will be |
| recorded correctly but it will be reported (e.g. via JMX) as |
| <code>-1</code> to make clear that it is not used.</p> |
| </attribute> |
| |
| <attribute name="minSpareThreads" required="false"> |
| <p>The minimum number of threads always kept running. If not specified, |
| the default of <code>10</code> is used. If an executor is associated |
| with this connector, this attribute is ignored as the connector will |
| execute tasks using the executor rather than an internal thread pool. Note |
| that if an executor is configured any value set for this attribute will be |
| recorded correctly but it will be reported (e.g. via JMX) as |
| <code>-1</code> to make clear that it is not used.</p> |
| </attribute> |
| |
| <attribute name="packetSize" required="false"> |
| <p>This attribute sets the maximum AJP packet size in Bytes. The maximum |
| value is 65536. It should be the same as the <code>max_packet_size</code> |
| directive configured for mod_jk. Normally it is not necessary to change |
| the maximum packet size. Problems with the default value have been |
| reported when sending certificates or certificate chains. The default |
| value is 8192. If set to less than 8192 then the setting will ignored and |
| the default value of 8192 used.</p> |
| </attribute> |
| |
| <attribute name="processorCache" required="false"> |
| <p>The protocol handler caches Processor objects to speed up performance. |
| This setting dictates how many of these objects get cached. |
| <code>-1</code> means unlimited, default is <code>200</code>. If not using |
| Servlet 3.0 asynchronous processing, a good default is to use the same as |
| the maxThreads setting. If using Servlet 3.0 asynchronous processing, a |
| good default is to use the larger of maxThreads and the maximum number of |
| expected concurrent requests (synchronous and asynchronous).</p> |
| </attribute> |
| |
| <attribute name="requiredSecret" required="false"> |
| <p>Only requests from workers with this secret keyword will be accepted. |
| </p> |
| </attribute> |
| |
| <attribute name="tcpNoDelay" required="false"> |
| <p>If set to <code>true</code>, the TCP_NO_DELAY option will be |
| set on the server socket, which improves performance under most |
| circumstances. This is set to <code>true</code> by default.</p> |
| </attribute> |
| |
| <attribute name="threadPriority" required="false"> |
| <p>The priority of the request processing threads within the JVM. |
| The default value is <code>5</code> (the value of the |
| <code>java.lang.Thread.NORM_PRIORITY</code> constant). See the JavaDoc |
| for the <code>java.lang.Thread</code> class for more details on what |
| this priority means.If an executor is associated |
| with this connector, this attribute is ignored as the connector will |
| execute tasks using the executor rather than an internal thread pool. Note |
| that if an executor is configured any value set for this attribute will be |
| recorded correctly but it will be reported (e.g. via JMX) as |
| <code>-1</code> to make clear that it is not used.</p> |
| </attribute> |
| |
| <attribute name="tomcatAuthentication" required="false"> |
| <p>If set to <code>true</code>, the authentication will be done in Tomcat. |
| Otherwise, the authenticated principal will be propagated from the native |
| webserver and used for authorization in Tomcat. Note that this principal |
| will have no roles associated with it. |
| The default value is <code>true</code>. If |
| <code>tomcatAuthorization</code> is set to <code>true</code> this |
| attribute has no effect.</p> |
| </attribute> |
| |
| <attribute name="tomcatAuthorization" required="false"> |
| <p>If set to <code>true</code>, the authenticated principal will be |
| propagated from the native webserver and considered already authenticated |
| in Tomcat. If the web application has one or more security constraints, |
| authorization will then be performed by Tomcat and roles assigned to the |
| authenticated principal. If the appropriate Tomcat Realm for the request |
| does not recognise the provided user name, a Principal will be still be |
| created but it will have no roles. The default value is |
| <code>false</code>.</p> |
| </attribute> |
| |
| </attributes> |
| |
| </subsection> |
| |
| <subsection name="Java TCP socket attributes"> |
| |
| <p>The BIO, NIO and NIO2 implementation support the following Java TCP socket |
| attributes in addition to the common Connector and HTTP attributes listed |
| above.</p> |
| |
| <attributes> |
| <attribute name="socket.rxBufSize" required="false"> |
| <p>(int)The socket receive buffer (SO_RCVBUF) size in bytes. JVM default |
| used if not set.</p> |
| </attribute> |
| <attribute name="socket.txBufSize" required="false"> |
| <p>(int)The socket send buffer (SO_SNDBUF) size in bytes. JVM default |
| used if not set.</p> |
| </attribute> |
| <attribute name="socket.tcpNoDelay" required="false"> |
| <p>(bool)This is equivalent to standard attribute |
| <strong>tcpNoDelay</strong>.</p> |
| </attribute> |
| <attribute name="socket.soKeepAlive" required="false"> |
| <p>(bool)Boolean value for the socket's keep alive setting |
| (SO_KEEPALIVE). JVM default used if not set.</p> |
| </attribute> |
| <attribute name="socket.ooBInline" required="false"> |
| <p>(bool)Boolean value for the socket OOBINLINE setting. JVM default |
| used if not set.</p> |
| </attribute> |
| <attribute name="socket.soReuseAddress" required="false"> |
| <p>(bool)Boolean value for the sockets reuse address option |
| (SO_REUSEADDR). JVM default used if not set.</p> |
| </attribute> |
| <attribute name="socket.soLingerOn" required="false"> |
| <p>(bool)Boolean value for the sockets so linger option (SO_LINGER). |
| A value for the standard attribute <strong>connectionLinger</strong> |
| that is >=0 is equivalent to setting this to <code>true</code>. |
| A value for the standard attribute <strong>connectionLinger</strong> |
| that is <0 is equivalent to setting this to <code>false</code>. |
| Both this attribute and <code>soLingerTime</code> must be set else the |
| JVM defaults will be used for both.</p> |
| </attribute> |
| <attribute name="socket.soLingerTime" required="false"> |
| <p>(int)Value in seconds for the sockets so linger option (SO_LINGER). |
| This is equivalent to standard attribute |
| <strong>connectionLinger</strong>. |
| Both this attribute and <code>soLingerOn</code> must be set else the |
| JVM defaults will be used for both.</p> |
| </attribute> |
| <attribute name="socket.soTimeout" required="false"> |
| <p>This is equivalent to standard attribute |
| <strong>connectionTimeout</strong>.</p> |
| </attribute> |
| <attribute name="socket.performanceConnectionTime" required="false"> |
| <p>(int)The first value for the performance settings. See |
| <a href="http://docs.oracle.com/javase/6/docs/api/java/net/Socket.html#setPerformancePreferences(int,%20int,%20int)">Socket Performance Options</a> |
| All three performance attributes must be set else the JVM defaults will |
| be used for all three.</p> |
| </attribute> |
| <attribute name="socket.performanceLatency" required="false"> |
| <p>(int)The second value for the performance settings. See |
| <a href="http://docs.oracle.com/javase/6/docs/api/java/net/Socket.html#setPerformancePreferences(int,%20int,%20int)">Socket Performance Options</a> |
| All three performance attributes must be set else the JVM defaults will |
| be used for all three.</p> |
| </attribute> |
| <attribute name="socket.performanceBandwidth" required="false"> |
| <p>(int)The third value for the performance settings. See |
| <a href="http://docs.oracle.com/javase/6/docs/api/java/net/Socket.html#setPerformancePreferences(int,%20int,%20int)">Socket Performance Options</a> |
| All three performance attributes must be set else the JVM defaults will |
| be used for all three.</p> |
| </attribute> |
| <attribute name="socket.unlockTimeout" required="false"> |
| <p>(int) The timeout for a socket unlock. When a connector is stopped, it will try to release the acceptor thread by opening a connector to itself. |
| The default value is <code>250</code> and the value is in milliseconds</p> |
| </attribute> |
| </attributes> |
| </subsection> |
| |
| <subsection name="NIO specific configuration"> |
| |
| <p>The following attributes are specific to the NIO connector.</p> |
| |
| <attributes> |
| |
| <attribute name="socket.directBuffer" required="false"> |
| <p>(bool)Boolean value, whether to use direct ByteBuffers or java mapped |
| ByteBuffers. Default is <code>false</code>.<br/> |
| When you are using direct buffers, make sure you allocate the |
| appropriate amount of memory for the direct memory space. On Sun's JDK |
| that would be something like <code>-XX:MaxDirectMemorySize=256m</code>. |
| </p> |
| </attribute> |
| |
| <attribute name="socket.appReadBufSize" required="false"> |
| <p>(int)Each connection that is opened up in Tomcat get associated with |
| a read ByteBuffer. This attribute controls the size of this buffer. By |
| default this read buffer is sized at <code>8192</code> bytes. For lower |
| concurrency, you can increase this to buffer more data. For an extreme |
| amount of keep alive connections, decrease this number or increase your |
| heap size.</p> |
| </attribute> |
| |
| <attribute name="socket.appWriteBufSize" required="false"> |
| <p>(int)Each connection that is opened up in Tomcat get associated with |
| a write ByteBuffer. This attribute controls the size of this buffer. By |
| default this write buffer is sized at <code>8192</code> bytes. For low |
| concurrency you can increase this to buffer more response data. For an |
| extreme amount of keep alive connections, decrease this number or |
| increase your heap size.<br/> |
| The default value here is pretty low, you should up it if you are not |
| dealing with tens of thousands concurrent connections.</p> |
| </attribute> |
| |
| <attribute name="socket.bufferPool" required="false"> |
| <p>(int)The NIO connector uses a class called NioChannel that holds |
| elements linked to a socket. To reduce garbage collection, the NIO |
| connector caches these channel objects. This value specifies the size of |
| this cache. The default value is <code>500</code>, and represents that |
| the cache will hold 500 NioChannel objects. Other values are |
| <code>-1</code> for unlimited cache and <code>0</code> for no cache.</p> |
| </attribute> |
| |
| <attribute name="socket.bufferPoolSize" required="false"> |
| <p>(int)The NioChannel pool can also be size based, not used object |
| based. The size is calculated as follows:<br/> |
| NioChannel |
| <code>buffer size = read buffer size + write buffer size</code><br/> |
| SecureNioChannel <code>buffer size = application read buffer size + |
| application write buffer size + network read buffer size + |
| network write buffer size</code><br/> |
| The value is in bytes, the default value is <code>1024*1024*100</code> |
| (100MB).</p> |
| </attribute> |
| |
| <attribute name="socket.processorCache" required="false"> |
| <p>(int)Tomcat will cache SocketProcessor objects to reduce garbage |
| collection. The integer value specifies how many objects to keep in the |
| cache at most. The default is <code>500</code>. Other values are |
| <code>-1</code> for unlimited cache and <code>0</code> for no cache.</p> |
| </attribute> |
| |
| <attribute name="socket.keyCache" required="false"> |
| <p>(int)Tomcat will cache KeyAttachment objects to reduce garbage |
| collection. The integer value specifies how many objects to keep in the |
| cache at most. The default is <code>500</code>. Other values are |
| <code>-1</code> for unlimited cache and <code>0</code> for no cache.</p> |
| </attribute> |
| |
| <attribute name="socket.eventCache" required="false"> |
| <p>(int)Tomcat will cache PollerEvent objects to reduce garbage |
| collection. The integer value specifies how many objects to keep in the |
| cache at most. The default is <code>500</code>. Other values are |
| <code>-1</code> for unlimited cache and <code>0</code> for no cache.</p> |
| </attribute> |
| |
| <attribute name="selectorPool.maxSelectors" required="false"> |
| <p>(int)The max selectors to be used in the pool, to reduce selector |
| contention. Use this option when the command line |
| <code>org.apache.tomcat.util.net.NioSelectorShared</code> value is set |
| to false. Default value is <code>200</code>.</p> |
| </attribute> |
| |
| <attribute name="selectorPool.maxSpareSelectors" required="false"> |
| <p>(int)The max spare selectors to be used in the pool, to reduce |
| selector contention. When a selector is returned to the pool, the system |
| can decide to keep it or let it be GC'd. Use this option when the |
| command line <code>org.apache.tomcat.util.net.NioSelectorShared</code> |
| value is set to false. Default value is <code>-1</code> (unlimited).</p> |
| </attribute> |
| |
| <attribute name="command-line-options" required="false"> |
| <p>The following command line options are available for the NIO |
| connector:<br/> |
| <code>-Dorg.apache.tomcat.util.net.NioSelectorShared=true|false</code> |
| - default is <code>true</code>. Set this value to <code>false</code> if you wish to |
| use a selector for each thread. When you set it to <code>false</code>, you can |
| control the size of the pool of selectors by using the |
| <strong>selectorPool.maxSelectors</strong> attribute.</p> |
| </attribute> |
| |
| </attributes> |
| </subsection> |
| |
| <subsection name="NIO2 specific configuration"> |
| |
| <p>The following attributes are specific to the NIO2 connector.</p> |
| |
| <attributes> |
| |
| <attribute name="useCaches" required="false"> |
| <p>(bool)Use this attribute to enable or disable object caching to |
| reduce the amount of GC objects produced. |
| The default value is <code>false</code>.</p> |
| </attribute> |
| |
| <attribute name="socket.directBuffer" required="false"> |
| <p>(bool)Boolean value, whether to use direct ByteBuffers or java mapped |
| ByteBuffers. Default is <code>false</code>.<br/> |
| When you are using direct buffers, make sure you allocate the |
| appropriate amount of memory for the direct memory space. On Sun's JDK |
| that would be something like <code>-XX:MaxDirectMemorySize=256m</code>. |
| </p> |
| </attribute> |
| |
| <attribute name="socket.appReadBufSize" required="false"> |
| <p>(int)Each connection that is opened up in Tomcat get associated with |
| a read ByteBuffer. This attribute controls the size of this buffer. By |
| default this read buffer is sized at <code>8192</code> bytes. For lower |
| concurrency, you can increase this to buffer more data. For an extreme |
| amount of keep alive connections, decrease this number or increase your |
| heap size.</p> |
| </attribute> |
| |
| <attribute name="socket.appWriteBufSize" required="false"> |
| <p>(int)Each connection that is opened up in Tomcat get associated with |
| a write ByteBuffer. This attribute controls the size of this buffer. By |
| default this write buffer is sized at <code>8192</code> bytes. For low |
| concurrency you can increase this to buffer more response data. For an |
| extreme amount of keep alive connections, decrease this number or |
| increase your heap size.<br/> |
| The default value here is pretty low, you should up it if you are not |
| dealing with tens of thousands concurrent connections.</p> |
| </attribute> |
| |
| <attribute name="socket.bufferPoolSize" required="false"> |
| <p>(int)The NIO2 connector uses a class called Nio2Channel that holds |
| elements linked to a socket. To reduce garbage collection, the NIO |
| connector caches these channel objects. This value specifies the size of |
| this cache. The default value is <code>500</code>, and represents that |
| the cache will hold 500 Nio2Channel objects. Other values are |
| <code>-1</code> for unlimited cache and <code>0</code> for no cache.</p> |
| </attribute> |
| |
| <attribute name="socket.processorCache" required="false"> |
| <p>(int)Tomcat will cache SocketProcessor objects to reduce garbage |
| collection. The integer value specifies how many objects to keep in the |
| cache at most. The default is <code>500</code>. Other values are |
| <code>-1</code> for unlimited cache and <code>0</code> for no cache.</p> |
| </attribute> |
| |
| <attribute name="socket.socketWrapperCache" required="false"> |
| <p>(int)Tomcat will cache SocketWrapper objects to reduce garbage |
| collection. The integer value specifies how many objects to keep in the |
| cache at most. The default is <code>500</code>. Other values are |
| <code>-1</code> for unlimited cache and <code>0</code> for no cache.</p> |
| </attribute> |
| |
| </attributes> |
| </subsection> |
| |
| <subsection name="APR/native specific configuration"> |
| |
| <p>The APR/native implementation supports the following attributes in |
| addition to the common Connector and AJP attributes listed above.</p> |
| |
| <attributes> |
| <attribute name="pollTime" required="false"> |
| <p>Duration of a poll call in microseconds. Lowering this value will |
| slightly decrease latency of connections being kept alive in some cases |
| , but will use more CPU as more poll calls are being made. The default |
| value is 2000 (2ms). |
| </p> |
| </attribute> |
| |
| <attribute name="pollerSize" required="false"> |
| <p>Amount of sockets that the poller responsible for polling kept alive |
| connections can hold at a given time. Extra connections will be closed |
| right away. The default value is 8192, corresponding to 8192 keep-alive |
| connections.</p> |
| </attribute> |
| |
| </attributes> |
| |
| </subsection> |
| |
| </section> |
| |
| |
| <section name="Nested Components"> |
| |
| <p>None at this time.</p> |
| |
| </section> |
| |
| <section name="Special Features"> |
| |
| <subsection name="Proxy Support"> |
| |
| <p>The <code>proxyName</code> and <code>proxyPort</code> attributes can |
| be used when Tomcat is run behind a proxy server. These attributes |
| modify the values returned to web applications that call the |
| <code>request.getServerName()</code> and <code>request.getServerPort()</code> |
| methods, which are often used to construct absolute URLs for redirects. |
| Without configuring these attributes, the values returned would reflect |
| the server name and port on which the connection from the proxy server |
| was received, rather than the server name and port to whom the client |
| directed the original request.</p> |
| |
| <p>For more information, see the |
| <a href="../proxy-howto.html">Proxy Support HOW-TO</a>.</p> |
| |
| </subsection> |
| |
| <subsection name="Connector Comparison"> |
| |
| <p>Below is a small chart that shows how the connectors differ.</p> |
| |
| <table class="defaultTable" style="text-align: center;"> |
| <tr> |
| <th /> |
| <th style="text-align: center;">Java Blocking Connector<br />BIO</th> |
| <th style="text-align: center;">Java Nio Connector<br />NIO</th> |
| <th style="text-align: center;">Java Nio2 Connector<br />NIO2</th> |
| <th style="text-align: center;">APR/native Connector<br />APR</th> |
| </tr> |
| <tr> |
| <th>Classname</th> |
| <td><code class="noHighlight">AjpProtocol</code></td> |
| <td><code class="noHighlight">AjpNioProtocol</code></td> |
| <td><code class="noHighlight">AjpNio2Protocol</code></td> |
| <td><code class="noHighlight">AjpAprProtocol</code></td> |
| </tr> |
| <tr> |
| <th>Tomcat Version</th> |
| <td>3.x onwards</td> |
| <td>7.x onwards</td> |
| <td>8.x onwards</td> |
| <td>5.5.x onwards</td> |
| </tr> |
| <tr> |
| <th>Support Polling</th> |
| <td>NO</td> |
| <td>YES</td> |
| <td>YES</td> |
| <td>YES</td> |
| </tr> |
| <tr> |
| <th>Polling Size</th> |
| <td>N/A</td> |
| <td><code class="noHighlight">maxConnections</code></td> |
| <td><code class="noHighlight">maxConnections</code></td> |
| <td><code class="noHighlight">maxConnections</code></td> |
| </tr> |
| <tr> |
| <th>Read Request Headers</th> |
| <td>Blocking</td> |
| <td>Blocking</td> |
| <td>Blocking</td> |
| <td>Blocking</td> |
| </tr> |
| <tr> |
| <th>Read Request Body</th> |
| <td>Blocking</td> |
| <td>Blocking</td> |
| <td>Blocking</td> |
| <td>Blocking</td> |
| </tr> |
| <tr> |
| <th>Write Response Headers and Body</th> |
| <td>Blocking</td> |
| <td>Blocking</td> |
| <td>Blocking</td> |
| <td>Blocking</td> |
| </tr> |
| <tr> |
| <th>Wait for next Request</th> |
| <td>Blocking</td> |
| <td>Non Blocking</td> |
| <td>Non Blocking</td> |
| <td>Non Blocking</td> |
| </tr> |
| <tr> |
| <th>Max Connections</th> |
| <td><code class="noHighlight">maxConnections</code></td> |
| <td><code class="noHighlight">maxConnections</code></td> |
| <td><code class="noHighlight">maxConnections</code></td> |
| <td><code class="noHighlight">maxConnections</code></td> |
| </tr> |
| </table> |
| |
| </subsection> |
| |
| </section> |
| |
| </body> |
| |
| </document> |