402075 Dont allocate the parser trie unless needed

jetty-client/src/main/java/org/eclipse/jetty/client/HttpReceiver.java

@@ -127,6 +127,14 @@ public class HttpReceiver implements HttpParser.ResponseHandler<ByteBuffer>
         }
     }
 
+
+    @Override
+    public int getHeaderCacheSize()
+    {
+        // TODO get from configuration
+        return 256;
+    }
+
     @Override
     public boolean startResponse(HttpVersion version, int status, String reason)
     {

jetty-http/src/main/java/org/eclipse/jetty/http/HttpParser.java

@@ -34,6 +34,7 @@ import org.eclipse.jetty.util.log.Logger;
 public class HttpParser
 {
     public static final Logger LOG = Log.getLogger(HttpParser.class);
+    private static final int INITIAL_URI_LENGTH=256;
 
     // States
     public enum State
@@ -80,7 +81,7 @@ public class HttpParser
     private HttpMethod _method;
     private String _methodString;
     private HttpVersion _version;
-    private ByteBuffer _uri=ByteBuffer.allocate(256); // Tune?
+    private ByteBuffer _uri=ByteBuffer.allocate(INITIAL_URI_LENGTH); // Tune?
     private byte _eol;
     private EndOfContent _endOfContent;
     private long _contentLength;
@@ -89,7 +90,7 @@ public class HttpParser
     private int _chunkPosition;
     private boolean _headResponse;
     private ByteBuffer _contentChunk;
-    private final Trie<HttpField> _connectionFields=new ArrayTernaryTrie<>(256);
+    private Trie<HttpField> _connectionFields;
 
     private int _length;
     private final StringBuilder _string=new StringBuilder();
@@ -513,6 +514,14 @@ public class HttpParser
                             return true;
                         }
                         
+                        // Should we try to cache header fields?
+                        if (_version.getVersion()>=HttpVersion.HTTP_1_1.getVersion())
+                        {
+                            int header_cache = _handler.getHeaderCacheSize();
+                            if (header_cache>0)
+                                _connectionFields=new ArrayTernaryTrie<>(header_cache);
+                        }
+
                         _eol=ch;
                         setState(State.HEADER);
                         _uri.flip();
@@ -592,7 +601,7 @@ public class HttpParser
                 break;
 
             case HOST:
-                add_to_connection_trie=_field==null;
+                add_to_connection_trie=_connectionFields!=null && _field==null;
                 _host=true;
                 String host=_valueString;
                 int port=0;
@@ -630,6 +639,12 @@ public class HttpParser
                 
               break;
               
+            case CONNECTION:
+                // Don't cache if not persistent
+                if (_valueString!=null && _valueString.indexOf("close")>=0)
+                    _connectionFields=null;
+                break;
+
             case AUTHORIZATION:
             case ACCEPT:
             case ACCEPT_CHARSET:
@@ -638,7 +653,7 @@ public class HttpParser
             case COOKIE:
             case CACHE_CONTROL:
             case USER_AGENT:
-                add_to_connection_trie=_field==null;
+                add_to_connection_trie=_connectionFields!=null && _field==null;
         }
     
         if (add_to_connection_trie && !_connectionFields.isFull() && _header!=null && _valueString!=null)
@@ -786,7 +801,7 @@ public class HttpParser
                                 if (buffer.remaining()>6)
                                 {
                                     // Try a look ahead for the known header name and value.
-                                    _field=_connectionFields.getBest(buffer,-1,buffer.remaining());
+                                    _field=_connectionFields==null?null:_connectionFields.getBest(buffer,-1,buffer.remaining());
                                     if (_field==null)
                                         _field=HttpField.CACHE.getBest(buffer,-1,buffer.remaining());
                                         
@@ -1396,6 +1411,11 @@ public class HttpParser
         public boolean earlyEOF();
 
         public void badMessage(int status, String reason);
+        
+        /* ------------------------------------------------------------ */
+        /** @return the size in bytes of the per parser header cache
+         */
+        public int getHeaderCacheSize();
     }
 
     public interface RequestHandler<T> extends HttpHandler<T>

jetty-http/src/main/java/org/eclipse/jetty/http/HttpTester.java

@@ -229,6 +229,12 @@ public class HttpTester
         }
         abstract public HttpGenerator.Info getInfo();
 
+        @Override
+        public int getHeaderCacheSize()
+        {
+            return 0;
+        }
+
     }
 
     public static class Request extends Message implements HttpParser.RequestHandler<ByteBuffer>

jetty-http/src/test/java/org/eclipse/jetty/http/HttpGeneratorServerTest.java

@@ -91,6 +91,12 @@ public class HttpGeneratorServerTest
         {
             throw new IllegalStateException(reason);
         }
+
+        @Override
+        public int getHeaderCacheSize()
+        {
+            return 256;
+        }
     }
 
     private static class TR

jetty-http/src/test/java/org/eclipse/jetty/http/HttpParserTest.java

@@ -926,5 +926,11 @@ public class HttpParserTest
         {
             return true;
         }
+
+        @Override
+        public int getHeaderCacheSize()
+        {
+            return 512;
+        }
     }
 }

jetty-server/src/main/config/etc/jetty.xml

@@ -82,6 +82,7 @@
       <Set name="responseHeaderSize">8192</Set>
       <Set name="sendServerVersion">true</Set>
       <Set name="sendDateHeader">false</Set>
+      <Set name="headerCacheSize">512</Set>
       
       <!-- Uncomment to enable handling of X-Forwarded- style headers 
       <Call name="addCustomizer">

jetty-server/src/main/java/org/eclipse/jetty/server/HttpChannel.java

@@ -167,6 +167,12 @@ public class HttpChannel<T> implements HttpParser.RequestHandler<T>, Runnable
         return _endPoint.getRemoteAddress();
     }
 
+    @Override
+    public int getHeaderCacheSize()
+    {
+        return _configuration.getHeaderCacheSize();
+    }
+    
     /**
      * If the associated response has the Expect header set to 100 Continue,
      * then accessing the input stream indicates that the handler/servlet

jetty-server/src/main/java/org/eclipse/jetty/server/HttpConfiguration.java

@@ -44,6 +44,7 @@ public class HttpConfiguration
     private int _outputBufferSize=32*1024;
     private int _requestHeaderSize=8*1024;
     private int _responseHeaderSize=8*1024;
+    private int _headerCacheSize=512;
     private int _securePort;
     private String _secureScheme = HttpScheme.HTTPS.asString();
     private boolean _sendServerVersion = true; //send Server: header
@@ -78,6 +79,7 @@ public class HttpConfiguration
         _secureScheme=config._secureScheme;
         _sendDateHeader=config._sendDateHeader;
         _sendServerVersion=config._sendServerVersion;
+        _headerCacheSize=config._headerCacheSize;
     }
     
     /* ------------------------------------------------------------ */
@@ -125,6 +127,12 @@ public class HttpConfiguration
         return _responseHeaderSize;
     }
 
+    @ManagedAttribute("The maximum allowed size in bytes for a HTTP header field cache")
+    public int getHeaderCacheSize()
+    {
+        return _headerCacheSize;
+    }
+
     @ManagedAttribute("The port to which Integral or Confidential security constraints are redirected")
     public int getSecurePort()
     {
@@ -210,6 +218,15 @@ public class HttpConfiguration
         _responseHeaderSize = responseHeaderSize;
     }
 
+    /* ------------------------------------------------------------ */
+    /** Set the header field cache size.
+     * @param headerCacheSize The size in bytes of the header field cache.
+     */
+    public void setHeaderCacheSize(int headerCacheSize)
+    {
+        _headerCacheSize = headerCacheSize;
+    }
+
     /* ------------------------------------------------------------ */
     /** Set the TCP/IP port used for CONFIDENTIAL and INTEGRAL 
      * redirections.

jetty-spdy/spdy-http-server/src/main/java/org/eclipse/jetty/spdy/server/proxy/ProxyHTTPSPDYConnection.java

@@ -150,6 +150,13 @@ public class ProxyHTTPSPDYConnection extends HttpConnection implements HttpParse
         return false;
     }
 
+    @Override
+    public int getHeaderCacheSize()
+    {
+        // TODO get from configuration
+        return 256;
+    }
+
     @Override
     public boolean earlyEOF()
     {