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本文主要研究一下tomcat的connection-timeout

ServerProperties.Tomcat

org/springframework/boot/autoconfigure/web/ServerProperties.java

	public static class Tomcat {/*** Access log configuration.*/private final Accesslog accesslog = new Accesslog();/*** Thread related configuration.*/private final Threads threads = new Threads();/*** Tomcat base directory. If not specified, a temporary directory is used.*/private File basedir;/*** Delay between the invocation of backgroundProcess methods. If a duration suffix* is not specified, seconds will be used.*/@DurationUnit(ChronoUnit.SECONDS)private Duration backgroundProcessorDelay = Duration.ofSeconds(10);/*** Maximum size of the form content in any HTTP post request.*/private DataSize maxHttpFormPostSize = DataSize.ofMegabytes(2);/*** Maximum amount of request body to swallow.*/private DataSize maxSwallowSize = DataSize.ofMegabytes(2);/*** Whether requests to the context root should be redirected by appending a / to* the path. When using SSL terminated at a proxy, this property should be set to* false.*/private Boolean redirectContextRoot = true;/*** Whether HTTP 1.1 and later location headers generated by a call to sendRedirect* will use relative or absolute redirects.*/private boolean useRelativeRedirects;/*** Character encoding to use to decode the URI.*/private Charset uriEncoding = StandardCharsets.UTF_8;/*** Maximum number of connections that the server accepts and processes at any* given time. Once the limit has been reached, the operating system may still* accept connections based on the "acceptCount" property.*/private int maxConnections = 8192;/*** Maximum queue length for incoming connection requests when all possible request* processing threads are in use.*/private int acceptCount = 100;/*** Maximum number of idle processors that will be retained in the cache and reused* with a subsequent request. When set to -1 the cache will be unlimited with a* theoretical maximum size equal to the maximum number of connections.*/private int processorCache = 200;/*** Comma-separated list of additional patterns that match jars to ignore for TLD* scanning. The special '?' and '*' characters can be used in the pattern to* match one and only one character and zero or more characters respectively.*/private List<String> additionalTldSkipPatterns = new ArrayList<>();/*** Comma-separated list of additional unencoded characters that should be allowed* in URI paths. Only "< > [ \ ] ^ ` { | }" are allowed.*/private List<Character> relaxedPathChars = new ArrayList<>();/*** Comma-separated list of additional unencoded characters that should be allowed* in URI query strings. Only "< > [ \ ] ^ ` { | }" are allowed.*/private List<Character> relaxedQueryChars = new ArrayList<>();/*** Amount of time the connector will wait, after accepting a connection, for the* request URI line to be presented.*/private Duration connectionTimeout;/*** Static resource configuration.*/private final Resource resource = new Resource();/*** Modeler MBean Registry configuration.*/private final Mbeanregistry mbeanregistry = new Mbeanregistry();/*** Remote Ip Valve configuration.*/private final Remoteip remoteip = new Remoteip();//......}	

springboot的ServerProperties.Tomcat定義了connectionTimeout屬性，用于指定接受連接之后等待uri的時間

customizeConnectionTimeout

org/springframework/boot/autoconfigure/web/embedded/TomcatWebServerFactoryCustomizer.java

	private void customizeConnectionTimeout(ConfigurableTomcatWebServerFactory factory, Duration connectionTimeout) {factory.addConnectorCustomizers((connector) -> {ProtocolHandler handler = connector.getProtocolHandler();if (handler instanceof AbstractProtocol) {AbstractProtocol<?> protocol = (AbstractProtocol<?>) handler;protocol.setConnectionTimeout((int) connectionTimeout.toMillis());}});}

customizeConnectionTimeout將connectionTimeout寫入到AbstractProtocol

AbstractProtocol

org/apache/coyote/AbstractProtocol.java

    public void setConnectionTimeout(int timeout) {endpoint.setConnectionTimeout(timeout);}

AbstractProtocol將timeout設置到endpoint

AbstractEndpoint

org/apache/tomcat/util/net/AbstractEndpoint.java

	public void setConnectionTimeout(int soTimeout) { socketProperties.setSoTimeout(soTimeout); }/*** Keepalive timeout, if not set the soTimeout is used.*/private Integer keepAliveTimeout = null;public int getKeepAliveTimeout() {if (keepAliveTimeout == null) {return getConnectionTimeout();} else {return keepAliveTimeout.intValue();}}

AbstractEndpoint將timeout設置到socketProperties的soTimeout，另外它的getKeepAliveTimeout方法在keepAliveTimeout為null的時候，使用的是getConnectionTimeout

Http11Processor

org/apache/coyote/http11/Http11Processor.java

    public SocketState service(SocketWrapperBase<?> socketWrapper)throws IOException {RequestInfo rp = request.getRequestProcessor();rp.setStage(org.apache.coyote.Constants.STAGE_PARSE);// Setting up the I/OsetSocketWrapper(socketWrapper);// FlagskeepAlive = true;openSocket = false;readComplete = true;boolean keptAlive = false;SendfileState sendfileState = SendfileState.DONE;while (!getErrorState().isError() && keepAlive && !isAsync() && upgradeToken == null &&sendfileState == SendfileState.DONE && !protocol.isPaused()) {// Parsing the request headertry {if (!inputBuffer.parseRequestLine(keptAlive, protocol.getConnectionTimeout(),protocol.getKeepAliveTimeout())) {if (inputBuffer.getParsingRequestLinePhase() == -1) {return SocketState.UPGRADING;} else if (handleIncompleteRequestLineRead()) {break;}}//......}//......}//......}          

Http11Processor的service方法在執行inputBuffer.parseRequestLine時傳入了keptAlive、protocol.getConnectionTimeout()、protocol.getKeepAliveTimeout()參數

小結

springboot提供了tomcat的connection-timeout參數配置，其配置的是socket timeout，不過springboot沒有提供對keepAliveTimeout的配置，它默認是null，讀取的是connection timeout的配置。