Attribute

Description

threadPriority （優先順序）

(int) The thread priority for threads in the executor, the default is 5 (the value of theThread.NORM_PRIORITY constant)

daemon（守護程序）

(boolean) Whether the threads should be daemon threads or not, the default is true

namePrefix（名稱字首）

(String) The name prefix for each thread created by the executor. The thread name for an individual thread will be namePrefix+threadNumber

maxThreads（最大執行緒數）

(int) The max number of active threads in this pool, default is 200

minSpareThreads（最小活躍執行緒數）

(int) The minimum number of threads always kept alive, default is 25

maxIdleTime（空閒執行緒等待時間）

(int) The number of milliseconds before an idle thread shutsdown, unless the number of active threads are less or equal to minSpareThreads. Default value is 60000(1 minute)

maxQueueSize（最大的等待隊裡數，超過則請求拒絕）

(int) The maximum number of runnable tasks that can queue up awaiting execution before we reject them. Default value is Integer.MAX_VALUE

prestartminSpareThreads

（是否在啟動時就生成minSpareThreads個執行緒）

(boolean) Whether minSpareThreads should be started when starting the Executor or not, the default is false

threadRenewalDelay

（重建執行緒的時間間隔）

(long) If a ThreadLocalLeakPreventionListener is configured, it will notify this executor about stopped contexts. After a context is stopped, threads in the pool are renewed. To avoid renewing all threads at the same time, this option sets a delay between renewal of any 2 threads. The value is in ms, default value is 1000 ms. If value is negative, threads are not renewed.

。重建執行緒池內的執行緒時，為了避免執行緒同時重建，每隔threadRenewalDelay（單位： ms ）重建一個執行緒。預設值為1000 ，設定為負則不重建

Attribute

Description

allowTrace

A boolean value which can be used to enable or disable the TRACE HTTP method. If not specified, this attribute is set to false.

如果需要伺服器能夠處理使用者的HAED/TRACE請求，這個值應該設定為true，預設值是false

asyncTimeout

The default timeout for asynchronous requests in milliseconds. If not specified, this attribute is set to 10000 (10 seconds).

預設超不時候以毫秒為單位的非同步懇求。若是沒有指定，該屬性被設定為10000（10秒）。

enableLookups

Set to true if you want calls to request.getRemoteHost() to perform DNS lookups in order to return the actual host name of the remote client. Set to false to skip the DNS lookup and return the IP address in String form instead (thereby improving performance). By default, DNS lookups are disabled.

若是你想request.getRemoteHost（）的呼叫 履行，以便返回的長途客戶端的實際主機名的DNS查詢，則設定為true。設定為false時跳過DNS查詢，並返回字串情勢的IP地址（從而提高效能）。預設景象下，禁用DNS查詢。

maxHeaderCount

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.

容器允許的請求頭欄位的最大數目。請求中包含比指定的限制更多的頭欄位將被拒絕。值小於0表示沒有限制。如果沒有指定，預設設定為100。

maxParameterCount

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 FailedRequestFilter filtercan be used to reject requests that hit the limit.

將被容器自動解析的最大數量的引數和值對（GET加上POST）。引數值對超出此限制將被忽略。值小於0表示沒有限制。如果沒有指定，預設為10000。請注意， FailedRequestFilter 過濾器可以用來拒絕達到了極限值的請求。

maxPostSize

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 or equal to 0. If not specified, this attribute is set to 2097152 (2 megabytes).

將被容器以FORM URL引數形式處理的最大長度（以位元組為單位）的POST。通過設定此屬性的值小於或等於0可以禁用該限制。如果沒有指定，該屬性被設定為2097152（2兆位元組）。

maxSavePostSize

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).

將被容器在FORM或CLIENT-CERT認證中儲存/緩衝的POST的最大尺寸（以位元組為單位）。對於這兩種型別的身份驗證，在使用者身份驗證之 前，POST將被儲存/緩衝。對於POST CLIENT-CERT認證，處理該請求的SSL握手和緩衝清空期間，POST將被快取。對於Form認證，POST將被儲存，同時使用者將被重定向到登陸 表單。POST將被一直保留直到使用者成功認證或者認證請求關聯的會話超時。將此屬性設定為-1可以禁用此限制。將此屬性設定為0，POST資料在身份驗證 過程中將不被儲存。如果沒有指定，該屬性設定為4096（4千位元組）。

parseBodyMethods

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 POST 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 POST

以逗號分隔的HTTP方法列表，通過方法列表，等同於POST方法，request 正文將被解析成請求引數。這在RESTful應用程式要支援以POST式的語義解析PUT請求中是非常有用的。需要注意的是設定其他值（不是POST）會導致Tomcat的行為違反servlet規範的目的。在這裡為了符合HTTP規範明確禁止HTTP方法TRACE。預設值是POST

port

The TCP port number on which this Connector 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.

TCP埠號，聯結器利用該埠號將建立一個伺服器套接字，並等待傳入的連線。你的作業系統將只允許一個伺服器應用程式在一個特定的IP地址偵聽特定的埠號。如果使用特殊值0（零），則Tomcat將為聯結器隨機選擇一個空閒的埠。這是通常只用在嵌入式和測試應用程式。

protocol

Sets the protocol to handle incoming traffic. The default value is HTTP/1.1 which uses an auto-switching mechanism to select either a blocking Java based connector or an APR/native based connector. If the PATH (Windows) or LD_LIBRARY_PATH (on most unix systems) environment variables contain the Tomcat native library, the APR/native connector will be used. If the native library cannot be found, the blocking Java based connector will be used. Note that the APR/native connector has different settings for HTTPS than the Java connectors.
To use an explicit protocol rather than rely on the auto-switching mechanism described above, the following values may be used:
org.apache.coyote.http11.Http11Protocol - blocking Java connector
org.apache.coyote.http11.Http11NioProtocol - non blocking Java connector
org.apache.coyote.http11.Http11AprProtocol - the APR/native connector.
Custom implementations may also be used.
Take a look at our Connector Comparison chart. The configuration for both Java connectors is identical, for http and https.
For more information on the APR connector and APR specific SSL settings please visit the APR documentation

設定協議來處理傳入流量。預設值是 HTTP/1.1，將使用自動切換機制來選擇阻塞的基於Java的聯結器或APR /native 為基礎的聯結器。如果PATH（Windows）或LD_LIBRARY_PATH（在大多數Unix系統）的環境變數包含在Tomcat的本地庫裡，APR /native 聯結器將被使用。如果在本地庫中無法找到，阻斷基於Java的聯結器將被使用。需要注意的是使用HTTPS比Java聯結器與APR /native 聯結器有不同的設定。一個明確的協議，而不是依靠上述自動切換機構，可用以下值：

org.apache.coyote.http11.Http11Protocol -阻塞式的Java聯結器
org.apache.coyote.http11.Http11NioProtocol -不阻塞Java聯結器
org.apache.coyote.http11.Http11AprProtocol的 -的APR / native 聯結器

 也可以使用的使用者自定義的實現。看一看在我們的聯結器比較圖。Java聯結器，HTTP和HTTPS，配置是相同的。 APR聯結器和APR特定的SSL設定的更多資訊，請訪問APR文件

proxyName

If this Connector is being used in a proxy configuration, configure this attribute to specify the server name to be returned for calls to request.getServerName(). See Proxy Support for more information.

如果這個連線正在使用的代理伺服器配置，配置該屬性指定的伺服器的名稱，可以呼叫request.getServerName（）返回。有關更多資訊，請參見代理支援。

proxyPort

If this Connector is being used in a proxy configuration, configure this attribute to specify the server port to be returned for calls to request.getServerPort(). See Proxy Support for more information.

如果這個連線正在使用的代理伺服器配置，配置該屬性指定伺服器埠，可以呼叫request.getServerPort（）返回。有關更多資訊，請參見代理支援。

redirectPort

If this Connector is supporting non-SSL requests, and a request is received for which a matching<security-constraint> requires SSL transport, Catalina will automatically redirect the request to the port number specified here.

如果該聯結器支援非SSL請求，並且接收到的請求為滿足安全約束需要SSL傳輸， Catalina 將自動將請求重定向到指定的埠號。

scheme

Set this attribute to the name of the protocol you wish to have returned by calls torequest.getScheme(). For example, you would set this attribute to "https" for an SSL Connector. The default value is "http".

將該屬性設定為你想呼叫request.getScheme（）返回的協議的名稱。例如，對於SSL聯結器，你會將此屬性設定為“HTTPS ”。預設值是“ HTTP ”。

secure

Set this attribute to true if you wish to have calls to request.isSecure() to return true 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 false.

如果你想呼叫request.isSecure（）收到此聯結器的請求返回true，請該該屬性設定為true。您希望SSL聯結器或非SSL聯結器接收資料通過一個SSL加速器，像加密卡，SSL裝置，甚至一個web伺服器。預設值是假的。

URIEncoding

This specifies the character encoding used to decode the URI bytes, after %xx decoding the URL. If not specified, ISO-8859-1 will be used.

這將指定使用的字元編碼​​，來解碼URI字元。如果沒有指定，ISO-8859-1將被使用。

useBodyEncodingForURI

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 false.

這指定是否應該用於URI查詢引數，而不是使用URIEncoding contentType中指定的編碼。此設定相容性Tomcat 4.1.x版（該版在contentType中指定編碼，或者使用request.setCharacterEncoding的方法顯式設定（引數為 URL傳來的值）。預設值false。

useIPVHosts

Set this attribute to true to cause Tomcat to use the IP address that the request was received on to determine the Host to send the request to. The default value is false.

將該屬性設定為true會導致Tomcat使用收到請求的IP地址，來確定將請求傳送到哪個主機。預設值是假的。

xpoweredBy

Set this attribute to true to cause Tomcat to advertise support for the Servlet specification using the header recommended in the specification. The default value is false.

將此屬性設定為true會導致Tomcat支援使用Servlet規範的通知，（在規範中推薦使用頭欄位）。預設值是假的。

Attribute

Description

acceptCount

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.

當所有可能的請求處理執行緒都在使用時，傳入連線請求的最大佇列長度。當佇列滿時收到的任何請求將被拒絕。預設值是100。

acceptorThreadCount

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 2. Also, with a lot of non keep alive connections, you might want to increase this value as well. Default value is 1.

用於接受連線的執行緒的數量。在一個多CPU的機器上，增加該值，雖然你可能不會真正需要超過2個。此外，有很多非保持活動連線，您可能需要增加這個值。預設值是 1。

acceptorThreadPriority

The priority of the acceptor threads. The threads used to accept new connections. The default value is 5 (the value of the java.lang.Thread.NORM_PRIORITY constant). See the JavaDoc for the java.lang.Thread class for more details on what this priority means.

接收器執行緒的優先順序。該執行緒用來接受新的連線。預設值是5（java.lang.Thread.NORM_PRIORITY常量）。更多這個優先順序是什麼意思的詳細資訊，請檢視java.lang.Thread的類的JavaDoc 。

address

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.

對於擁有多個IP地址的伺服器，該屬性指定哪個地址將被用於在指定埠上監聽。預設情況下，該埠將被用於與伺服器相關聯的所有IP地址。

bindOnInit

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 false, the socket will be bound when the connector is started and unbound when it is stopped.

控制聯結器繫結時套接字的使用。預設情況，當聯結器被啟動時套接字被繫結和當聯結器被銷燬時套接字解除繫結。如果設定為false，聯結器啟動時套接字被繫結，聯結器停止時套接字解除繫結。

compressableMimeType

The value is a comma separated list of MIME types for which HTTP compression may be used. The default value is text/html,text/xml,text/plain.

該值是一個被用於HTTP壓縮的逗號分隔的MIME型別列表。預設值是text / html型別，為text / xml，text / plain。

compression

The Connector may use HTTP/1.1 GZIP compression in an attempt to save server bandwidth. The acceptable values for the parameter is "off" (disable compression), "on" (allow compression, which causes text data to be compressed), "force" (forces compression in all cases), or a numerical integer value (which is equivalent to "on", but specifies the minimum amount of data before the output is compressed). If the content-length is not known and compression is set to "on" or more aggressive, the output will also be compressed. If not specified, this attribute is set to "off".

Note: There is a tradeoff between using compression (saving your bandwidth) and using the sendfile feature (saving your CPU cycles). If the connector supports the sendfile feature, e.g. the NIO connector, using sendfile will take precedence over compression. The symptoms will be that static files greater that 48 Kb will be sent uncompressed. You can turn off sendfile by setting useSendfile attribute of the connector, as documented below, or change the sendfile usage threshold in the configuration of the DefaultServlet in the defaultconf/web.xml or in the web.xml of your web application.

為了節省伺服器頻寬，聯結器可以使用HTTP/1.1 GZIP壓縮。可接受的引數的值是“off ”（禁用壓縮），“on ”（允許壓縮，這會導致文字資料被壓縮），“force ”（強制在所有的情況下壓縮），或者一個整數值（這是相當於為“on”，但指定了輸出之前被壓縮的資料最小量）。如果不知道內容長度但被設定為“on”或更積極的壓縮，輸出的資料也將被壓縮。如果沒有指定，該屬性被設定為“關”。

注意：這是使用壓縮（節省您的頻寬）和使用sendfile功能（節省你的CPU週期）之間的權衡。如果聯結器支援sendfile功能，例如NIO連線，則使用sendfile將優先於壓縮。症狀是48 KB的靜態檔案將未壓縮就傳送。你可以如下文所述通過設定聯結器的useSendfile屬性來關閉sendfile，或在預設的conf/web.xml或者你的web應用的web.xml中配置DefaultServlet來改變sendfile的使用量閾值。

compressionMinSize

If compression is set to "on" then this attribute may be used to specify the minimum amount of data before the output is compressed. If not specified, this attribute is defaults to "2048".

如果壓縮被設定為“on”，那麼該屬性可以用於指定在輸出之前被壓縮的資料的最小量。如果未指定，此屬性預設為“2048”。

connectionLinger

The number of seconds during which the sockets used by this Connector will linger when they are closed. The default value is -1 which disables socket linger.

聯結器的套接字被關閉時的逗留秒數。如果沒有指定，將使用預設的JVM。

connectionTimeout

The number of milliseconds this Connector will wait, after accepting a connection, for the request URI line to be presented. Use a value of -1 to indicate no (i.e. infinite) timeout. The default value is 60000 (i.e. 60 seconds) but note that the standard server.xml that ships with Tomcat sets this to 20000 (i.e. 20 seconds). UnlessdisableUploadTimeout is set to false, this timeout will also be used when reading the request body (if any).

在將提交的請求URI行呈現之後，聯結器將等待接受連線的毫秒數。使用值-1表示沒有超時（即無限）。預設值是60000（60秒），但請注意，Tomcat的標準server.xml中，設定為20000（即20秒）。

connectionUploadTimeout

Specifies the timeout, in milliseconds, to use while a data upload is in progress. This only takes effect if disableUploadTimeout is set to false.

上傳資料過程中，指定的以毫秒為單位超時時間。只有在設定disableUploadTimeout為false有效。

disableUploadTimeout

This flag allows the servlet container to use a different, usually longer connection timeout during data upload. If not specified, this attribute is set to true which disables this longer timeout.

此標誌允許servlet容器在資料上傳時使用不同的連線超時，通常較長。如果沒有指定，該屬性被設定為true，禁用上傳超時。

executor

A reference to the name in an Executor 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.

指向Executor元素的引用。如果這個屬性被設定，並且被命名的executor存在，聯結器將使用這個executor，而其他所有執行緒相關屬性將被忽略。請注意共享的executor如果沒有指定到一個聯結器，則該聯結器將使用一個私有的，內部的executor來提供執行緒池。

executorTerminationTimeoutMillis

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 0 (zero) for the BIO connector and 5000 (5 seconds) for the NIO and APR/native connectors.

keepAliveTimeout

The number of milliseconds this Connector will wait for another HTTP request before closing the connection. The default value is to use the value that has been set for theconnectionTimeout attribute. Use a value of -1 to indicate no (i.e. infinite) timeout.

此聯結器在關閉連線之前將等待另一個HTTP請求的毫秒數。預設值是使用已設定的connectionTimeout屬性的值。使用值-1表示沒有超時（即無限）。

maxConnections

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 maxConnections 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 acceptCount setting. The default value varies by connector type. For BIO the default is the value of maxThreads unless anExecutor is used in which case the default will be the value of maxThreads from the executor. For NIO the default is 10000. For APR/native, the default is 8192.

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.
If set to a value of -1, the maxConnections feature is disabled and connections are not counted.

在任何給定的時間伺服器接受並處理的最大連線數。當這個數字已經達到了，伺服器將不會接受任何連線，直到連線的數量降到低於此值。基於acceptCount的設定，作業系統可能仍然接受連線。預設值根據不同的聯結器型別而不同。對於BIO，預設的是maxThreads的值，除非使用了Executor，在這種情況下預設值是executor的maxThreads值 。對於NIO的預設值是10000。APR /native的預設值是8192。

需要注意的是Windows系統的APR/native，所配置的值將減少到小於或等於maxConnections的1024的倍數的最大值。這樣做是出於效能方面的考慮。

如果設定的值-1，maxConnections功能被禁用，而且連線數將不做計算。

maxExtensionSize

Limits the total length of chunk extensions in chunked HTTP requests. If the value is -1, no limit will be imposed. If not specified, the default value of 8192 will be used.

maxHttpHeaderSize

The maximum size of the request and response HTTP header, specified in bytes. If not specified, this attribute is set to 8192 (8 KB).

請求和響應的HTTP頭的（以位元組為單位的）最大尺寸。如果沒有指定，該屬性被設定為8192（8 KB）。

maxKeepAliveRequests

The maximum number of HTTP requests which can be pipelined until the connection is closed by the server. Setting this attribute to 1 will disable HTTP/1.0 keep-alive, as well as HTTP/1.1 keep-alive and pipelining. Setting this to -1 will allow an unlimited amount of pipelined or keep-alive HTTP requests. If not specified, this attribute is set to 100.

HTTP請求最大長連線個數。將此屬性設定為1，將禁用HTTP/1.0、以及HTTP/1.1的長連線。設定為-1，不禁用。如果沒有指定，該屬性被設定為100。

maxSwallowSize

The maximum number of request body bytes (excluding transfer encoding overhead) that will be swallowed by Tomcat for an aborted upload. An aborted upload is when Tomcat knows that the request body is going to be ignored but the client still sends it. If Tomcat does not swallow the body the client is unlikely to see the response. If not specified the default of 2097152 (2 megabytes) will be used. A value of less than zero indicates that no limit should be enforced.

maxThreads

The maximum number of request processing threads to be created by this Connector, 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.

最多同時處理的連線數，Tomcat使用執行緒來處理接收的每個請求。這個值表示Tomcat可建立的最大的執行緒數。如果沒有指定，該屬性被設定為200。如果使用了execute將忽略此聯結器的該屬性，聯結器將使用execute，而不是一個內部執行緒池來處理請求。

maxTrailerSize

Limits the total length of trailing headers in the last chunk of a chunked HTTP request. If the value is -1, no limit will be imposed. If not specified, the default value of 8192will be used.

限制一個分塊的HTTP請求中的最後一個塊的尾隨標頭的總長度。如果該值是-1，沒有限制的被強加。如果沒有指定，預設值是8192。

minSpareThreads

The minimum number of threads always kept running. If not specified, the default of 10 is used.

始終保持執行最小執行緒數。如果沒有指定，則預設為10。

noCompressionUserAgents

The value is a regular expression (using java.util.regex) matching the user-agent header of HTTP clients for which compression should not be used, because these clients, although they do advertise support for the feature, have a broken implementation. The default value is an empty String (regexp matching disabled).

該值是一個正則表示式（使用java.util.regex），匹配不應該使用壓縮的HTTP客戶端的使用者代理標頭。因為這些客戶端，雖然他們宣稱支援壓縮功能，但實現不完整。預設值是一個空字串（正則表示式匹配禁用）。

processorCache

The protocol handler caches Processor objects to speed up performance. This setting dictates how many of these objects get cached. -1 means unlimited, default is 200. 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).

協議處理器快取Processor物件以提高效能。此設定規定了這些物件有多少能得到快取。-1意味著無限制，預設為200。如果不使用Servlet 3.0的非同步處理，一個好的預設是使用maxThreads設定。如果使用Servlet 3.0的非同步處理，一個好的預設是使用maxThreads和最大預期的併發請求（同步和非同步）的最大值中的較大值。

restrictedUserAgents

The value is a regular expression (using java.util.regex) matching the user-agent header of HTTP clients for which HTTP/1.1 or HTTP/1.0 keep alive should not be used, even if the clients advertise support for these features. The default value is an empty String (regexp matching disabled).

該值是一個正則表示式（使用java.util.regex），匹配使用者代理頭的HTTP瀏覽器將不能使用HTTP/1.1或HTTP/1.0長連線，即使該瀏覽器宣稱支援這些功能的。預設值是一個空字串（正則表示式匹配禁用）。

server

Overrides the Server header for the http response. If set, the value for this attribute overrides the Tomcat default and any Server header set by a web application. If not set, any value specified by the application is used. If the application does not specify a value then Apache-Coyote/1.1 is used. Unless you are paranoid, you won't need this feature.

覆蓋伺服器的HTTP響應頭。如果設定了這個屬性的值將覆蓋Web應用程式設定的Tomcat的預設頭和任何伺服器頭。如果沒有設定，應用程式指定的任何值將被使用。如果應用程式沒有指定一個值，那麼Apache-Coyote/1.1將被使用。除非你是偏執狂，你將不再需要此功能。

socketBuffer

The size (in bytes) of the buffer to be provided for socket output buffering. -1 can be specified to disable the use of a buffer. By default, a buffers of 9000 bytes will be used.

為套接字輸出緩衝而提供的緩衝區的大小（以位元組為單位）。-1可以被指定來禁止使用的緩衝區。預設情況下，一個9000個位元組的緩衝區將被使用。

SSLEnabled

Use this attribute to enable SSL traffic on a connector. To turn on SSL handshake/encryption/decryption on a connector set this value to true. The default value is false. When turning this value true you will want to set the scheme and the secureattributes as well to pass the correct request.getScheme() and request.isSecure() values to the servlets See SSL Support for more information.

在聯結器上使用此屬性來啟用SSL加密傳輸。如果要開啟SSL握手/加密/解密，請設定true。預設值是false。當設定這個值為true時，為了傳遞正確的request.getScheme（）和 request.isSecure（）到servlets，你需要設定scheme和secure屬性。更多資訊請檢視SSL支援。

tcpNoDelay

If set to true, the TCP_NO_DELAY option will be set on the server socket, which improves performance under most circumstances. This is set to true by default.

如果設定為true，TCP_NO_DELAY選項將被設定在伺服器上的套接字上，在大多數情況下，這樣可以提高效能。預設設定為true。

threadPriority

The priority of the request processing threads within the JVM. The default value is 5(the value of the java.lang.Thread.NORM_PRIORITY constant). See the JavaDoc for thejava.lang.Thread class for more details on what this priority means.

在JVM中請求處理執行緒的優先順序。預設值是5（java.lang.Thread.NORM_PRIORITY常量值）。關於優先順序的更多詳細資訊，請檢視java.lang.Thread的類的JavaDoc 。

upgradeAsyncWriteBufferSize

The default size of the buffer to allocate to for asynchronous writes that can not be completed in a single operation. Data that can't be written immediately will be stored in this buffer until it can be written. If more data needs to be stored than space is available in the buffer than the size of the buffer will be increased for the duration of the write. If not specified the default value of 8192 will be used.

Attribute

Description

pollerThreadCount

(int)The number of threads to be used to run for the polling events. Default value is 1 per processor up to and including version 7.0.27. Default value as of version 7.0.28 is 1 per processor but not more than 2.
When accepting a socket, the operating system holds a global lock. So the benefit of going above 2 threads diminishes rapidly. Having more than one thread is for system that need to accept connections very rapidly. However usually just increasing acceptCount will solve that problem. Increasing this value may also be beneficial when a large amount of send file operations are going on.

（int）用來處理輪詢事件的執行緒的數量。在版本7.0.27及以前版本，預設值是每個處理器1個。版本7.0.28的預設值是每個處理器1個，但不超過2個。

當接受一個套接字，作業系統擁有全域性的鎖。所以超過2個執行緒的好處而迅速減小。有一個以上的執行緒是因為系統需要非常迅速地接受連線。但通常只要增加acceptCount值就可以解決這個問題。增加該值也可能是有用的，當大量傳送檔案操作發生的時候。

pollerThreadPriority

(int)The priority of the poller threads. The default value is 5 (the value of thejava.lang.Thread.NORM_PRIORITY constant). See the JavaDoc for the java.lang.Thread class for more details on what this priority means.

（int）輪詢執行緒的優先順序。預設值是5（java.lang.Thread.NORM_PRIORITY常量值）。優先順序的更多詳細資訊，可以查考java.lang.Thread類的JavaDoc 。

selectorTimeout

(int)The time in milliseconds to timeout on a select() for the poller. This value is important, since connection clean up is done on the same thread, so do not set this value to an extremely high one. The default value is 1000 milliseconds.

（int）選擇輪詢器select（）的超時時間（以毫秒為單位）。這個值非常重要，因為連線清理工作也是在同一個執行緒裡的，所以不要將此值設定為一個非常高的。預設值是1000毫秒。

useComet

(bool)Whether to allow comet servlets or not. Default value is true.

（bool）是否允許Comet servlet。預設值是 true。

useSendfile

(bool)Use this attribute to enable or disable sendfile capability. The default value istrue.

（bool）使用此屬性來啟用或禁用sendfile的能力。預設值是true。

socket.directBuffer

(bool)Boolean value, whether to use direct ByteBuffers or java mapped ByteBuffers. Default is false.
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 -XX:MaxDirectMemorySize=256m.

（bool）選擇使​​用直接ByteBuffers或Java對映的ByteBuffers。預設是false。

當您使用直接ByteBuffers，請確保你分配適當的記憶體量給直接記憶體空間。在Sun的JDK中，配置如-XX：MaxDirectMemorySize = 256M。

socket.appReadBufSize

(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 at8192 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.

（int）在Tomcat中每個連線的開闢連線一個讀ByteBuffer。此屬性控制這個緩衝區的大小。預設情況下，這個讀緩衝區大小為8192位元組。對於較低的併發，你可以增加這個值以緩衝更多的資料。對於長連線數很多的情況，你需要降低這個數值或者增加堆大小。

socket.appWriteBufSize

(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 at8192 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.
The default value here is pretty low, you should up it if you are not dealing with tens of thousands concurrent connections.

（int）在Tomcat中每個連線的開闢連線一個寫ByteBuffer。此屬性控制這個緩衝區的大小。預設情況下，這個寫緩衝區大小為8192位元組。對於較低的併發，你可以增加這個值以緩衝更多的響應資料。對於長連線數很多的情況，你需要降低這個數值或者增加堆大小。

這裡的預設值是相當低的，如果面對的不是幾萬併發連線，你應該增大該值。

socket.bufferPool

(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 500, and represents that the cache will hold 500 NioChannel objects. Other values are -1 for unlimited cache and 0 for no cache.

（int）NIO聯結器使用NioChannel這個類來持有連結到一個套接字的元素。為了減少垃圾收集，NIO聯結器快取這些通道的物件。此值指定這個快取的大小。預設值是500，表示快取將持有500個 NioChannel的物件。-1表示不限制快取大小，0表示不快取。

socket.bufferPoolSize

(int)The NioChannel pool can also be size based, not used object based. The size is calculated as follows:
NioChannel buffer size = read buffer size + write buffer size
SecureNioChannel buffer size = application read buffer size + application write buffer size + network read buffer size + network write buffer size
The value is in bytes, the default value is 1024*1024*100 (100MB).

（int）NioChannel池，也可以是基於尺寸大小，而不是基於物件數的。該大小的計算如下：

NioChannel的緩衝區大小=讀取緩衝區大小+寫入緩衝區大小

SecureNioChannel的緩衝區大小=應用程式讀取緩衝區大小+應用程式寫入緩衝區的大小+網路讀取緩衝區大小+網路寫入緩衝區的大小

值（以位元組為單位），預設值1024 * 1024 * 100 （100MB）。

socket.processorCache

(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 500. Other values are -1 for unlimited cache and 0 for no cache.

（int）以減少垃圾收集，Tomcat快取SocketProcessor物件。該值指定保持在快取中最多有多少個物件。預設值是500。-1表示不限制快取大小，0表示不快取。

socket.keyCache

(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 500. Other values are -1 for unlimited cache and 0 for no cache.

（int）以減少垃圾收集，Tomcat快取KeyAttachment物件。該值指定保持在快取中最多有多少個物件。預設值是500。-1表示不限制快取大小，0表示不快取。

socket.eventCache

(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 500. Other values are -1 for unlimited cache and 0 for no cache.

（int）以減少垃圾收集，Tomcat快取PollerEvent物件。該值指定保持在快取中最多有多少個物件。預設值是500。-1表示不限制快取大小，0表示不快取。

selectorPool.maxSelectors

(int)The max selectors to be used in the pool, to reduce selector contention. Use this option when the command line org.apache.tomcat.util.net.NioSelectorShared value is set to false. Default value is 200.

（int）以減少選擇器的爭用，在池中使用的選擇器最大個數。命令列org.apache.tomcat.util.net.NioSelectorShared值設定為false時，使用此選項。預設值是200。

selectorPool.maxSpareSelectors

(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 org.apache.tomcat.util.net.NioSelectorShared value is set to false. Default value is -1 (unlimited).

（int）以減少選擇器的爭用，在池中使用的最大備用選擇器個數。當選擇器返回到池中時，系統可以決定保留它或者讓他垃圾回收。當org.apache.tomcat.util.net.NioSelectorShared 值設定為false時，使用此選項。預設值是-1（無限制）。

command-line-options

The following command line options are available for the NIO connector:
-Dorg.apache.tomcat.util.net.NioSelectorShared=true|false - default is true. Set this value to false if you wish to use a selector for each thread. When you set it to false, you can control the size of the pool of selectors by using the selectorPool.maxSelectors attribute.

下面的命令列選項可用於NIO聯結器：-Dorg.apache.tomcat.util.net.NioSelectorShared=true|false

 預設情況下是true。如果你想每個執行緒使用一個選擇器，將此值設定為false。當你將它設定為false，你可以通過使用selectorPool.maxSelectors屬性控制選擇器池的大小。

oomParachute

(int)The NIO connector implements an OutOfMemoryError strategy called parachute. It holds a chunk of data as a byte array. In case of an OOM, this chunk of data is released and the error is reported. This will give the VM enough room to clean up. The oomParachute represents the size in bytes of the parachute(the byte array). The default value is 1024*1024(1MB). Please note, this only works for OOM errors regarding the Java Heap space, and there is absolutely no guarantee that you will be able to recover at all. If you have an OOM outside of the Java Heap, then this parachute trick will not help.

（int）NIO聯結器實現了一個名叫parachute的OutOfMemoryError錯誤的策略。它擁有一個塊的資料作為一個位元組陣列。在一個OOM的情況下，這個資料塊被釋放，並報告錯誤。這會給VM足夠的空間來清理。oomParachute代表parachute（位元組陣列）的大小（以位元組為單位）。預設值是 1024 * 1024（1MB）。請注意，這僅適用於關於Java堆空間的OOM錯誤，也不是絕對保證，你將能夠恢復所有。如果你有一個Java堆之外OOM的，那麼這個parachute也無濟於事。