Speed up secure sockets by increasing encrypted buffer size.

sdk/lib/io/secure_socket.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of dart.io;
 
 /**
  * SecureSocket provides a secure (SSL or TLS) client connection to a server.
  * The certificate provided by the server is checked
  * using the certificate database (optionally) provided in initialize().
@@ skipping 623 matching lines @@
   Function _socketDataHandler;
   Function _socketErrorHandler;
   Function _socketCloseHandler;
   Timer scheduledDataEvent;
 
   _SecureFilter secureFilter;
 }
 
 
 class _ExternalBuffer {
+  // Performance is improved if a full buffer of plaintext fits
+  // in the encrypted buffer, when encrypted.
   static final int SIZE = 8 * 1024;
+  static final int ENCRYPTED_SIZE = 10 * 1024;
   _ExternalBuffer() : start = 0, length = 0;
 
   // TODO(whesse): Consider making this a circular buffer.  Only if it helps.
   void advanceStart(int numBytes) {
     start += numBytes;
     length -= numBytes;
     if (length == 0) {
       start = 0;
     }
   }
 
-  int get free => SIZE - (start + length);
+  int get free => data.length - (start + length);
 
   List data;  // This will be a ExternalByteArray, backed by C allocated data.
   int start;
   int length;
 }
 
 
 abstract class _SecureFilter {
   external factory _SecureFilter();
 
   void connect(String hostName,
                int port,
                bool is_server,
                String certificateName,
                bool requestClientCertificate,
                bool requireClientCertificate,
                bool sendClientCertificate);
   void destroy();
   void handshake();
   void init();
   X509Certificate get peerCertificate;
   int processBuffer(int bufferIndex);
   void registerBadCertificateCallback(Function callback);
   void registerHandshakeCompleteCallback(Function handshakeCompleteHandler);
 
   List<_ExternalBuffer> get buffers;
 }