able to adjust tomcat acceptor count

apollo-biz/src/main/java/com/ctrip/apollo/biz/customize/TomcatContainerCustomizer.java

+package com.ctrip.apollo.biz.customize;
+
+import org.apache.catalina.connector.Connector;
+import org.apache.coyote.ProtocolHandler;
+import org.apache.coyote.http11.Http11NioProtocol;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.context.embedded.ConfigurableEmbeddedServletContainer;
+import org.springframework.boot.context.embedded.EmbeddedServletContainerCustomizer;
+import org.springframework.boot.context.embedded.tomcat.TomcatConnectorCustomizer;
+import org.springframework.boot.context.embedded.tomcat.TomcatEmbeddedServletContainerFactory;
+import org.springframework.core.env.Environment;
+import org.springframework.stereotype.Component;
+
+/**
+ * @author Jason Song(song_s@ctrip.com)
+ */
+@Component
+public class TomcatContainerCustomizer implements EmbeddedServletContainerCustomizer {
+  private static final String TOMCAT_ACCEPTOR_COUNT = "server.tomcat.acceptor-count";
+  @Autowired
+  private Environment environment;
+
+  @Override
+  public void customize(ConfigurableEmbeddedServletContainer container) {
+    if (!(container instanceof TomcatEmbeddedServletContainerFactory)) {
+      return;
+    }
+    if (!environment.containsProperty(TOMCAT_ACCEPTOR_COUNT)) {
+      return;
+    }
+    TomcatEmbeddedServletContainerFactory tomcat =
+        (TomcatEmbeddedServletContainerFactory) container;
+    tomcat.addConnectorCustomizers(new TomcatConnectorCustomizer() {
+      @Override
+      public void customize(Connector connector) {
+        ProtocolHandler handler = connector.getProtocolHandler();
+        if (handler instanceof Http11NioProtocol) {
+          Http11NioProtocol http = (Http11NioProtocol) handler;
+          http.setBacklog(Integer.parseInt(environment.getProperty(TOMCAT_ACCEPTOR_COUNT)));
+        }
+
+      }
+    });
+  }
+}

apollo-biz/src/main/resources/application.properties

@@ -7,3 +7,6 @@ spring.datasource.validationQuery=SELECT 1
 spring.jpa.hibernate.naming_strategy=org.hibernate.cfg.EJB3NamingStrategy
 spring.jpa.hibernate.globally_quoted_identifiers=true
 spring.jpa.properties.hibernate.globally_quoted_identifiers=true
+
+# Tomcat configuration
+server.tomcat.acceptor-count=1024