Provide a configuration property for configuring Tomcat's processor cache

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/ServerProperties.java

@@ -56,6 +56,7 @@
  * @author Brian Clozel
  * @author Olivier Lamy
  * @author Chentao Qu
+ * @author Artsiom Yudovin
  */
 @ConfigurationProperties(prefix = "server", ignoreUnknownFields = true)
 public class ServerProperties {
@@ -381,6 +382,19 @@ public static class Tomcat {
 		 */
 		private final Resource resource = new Resource();
 
+		/**
+		 * Configuring processor cache.
+		 */
+		private int processorCache = 200;
+
+		public int getProcessorCache() {
+			return this.processorCache;
+		}
+
+		public void setProcessorCache(int processorCache) {
+			this.processorCache = processorCache;
+		}
+
 		public int getMaxThreads() {
 			return this.maxThreads;
 		}

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/embedded/TomcatWebServerFactoryCustomizer.java

@@ -108,6 +108,8 @@ public void customize(ConfigurableTomcatWebServerFactory factory) {
 				.to((maxConnections) -> customizeMaxConnections(factory, maxConnections));
 		propertyMapper.from(tomcatProperties::getAcceptCount).when(this::isPositive)
 				.to((acceptCount) -> customizeAcceptCount(factory, acceptCount));
+		propertyMapper.from(tomcatProperties::getProcessorCache).when(this::isPositive)
+				.to((processorCache) -> customizeProcessorCache(factory, processorCache));
 		customizeStaticResources(factory);
 		customizeErrorReportValve(properties.getError(), factory);
 	}
@@ -156,6 +158,13 @@ private void customizeConnectionTimeout(ConfigurableTomcatWebServerFactory facto
 		});
 	}
 
+	private void customizeProcessorCache(ConfigurableTomcatWebServerFactory factory,
+			int processorCache) {
+		factory.addConnectorCustomizers((
+				connector) -> ((AbstractHttp11Protocol<?>) connector.getProtocolHandler())
+						.setProcessorCache(processorCache));
+	}
+
 	private void customizeRemoteIpValve(ConfigurableTomcatWebServerFactory factory) {
 		Tomcat tomcatProperties = this.serverProperties.getTomcat();
 		String protocolHeader = tomcatProperties.getProtocolHeader();

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/embedded/TomcatWebServerFactoryCustomizerTests.java

@@ -280,6 +280,12 @@ public void testCustomizeMinSpareThreads() {
 		assertThat(this.serverProperties.getTomcat().getMinSpareThreads()).isEqualTo(10);
 	}
 
+	@Test
+	public void testCustomizeProcessorCache() {
+		bind("server.tomcat.processor-cache=100");
+		assertThat(this.serverProperties.getTomcat().getProcessorCache()).isEqualTo(100);
+	}
+
 	@Test
 	public void accessLogBufferingCanBeDisabled() {
 		bind("server.tomcat.accesslog.enabled=true",

spring-boot-project/spring-boot-docs/src/main/asciidoc/appendix-application-properties.adoc

@@ -284,6 +284,7 @@ content into your application. Rather, pick only the properties that you need.
 	server.tomcat.resource.cache-ttl= # Time-to-live of the static resource cache.
 	server.tomcat.uri-encoding=UTF-8 # Character encoding to use to decode the URI.
 	server.tomcat.use-relative-redirects= # Whether HTTP 1.1 and later location headers generated by a call to sendRedirect will use relative or absolute redirects.
+	server.tomcat.processor-cache= # Custom value for Tomcat's processor cache.
 	server.undertow.accesslog.dir= # Undertow access log directory.
 	server.undertow.accesslog.enabled=false # Whether to enable the access log.
 	server.undertow.accesslog.pattern=common # Format pattern for access logs.