From 90295d9fce277a306149b185bd46a77eac818322 Mon Sep 17 00:00:00 2001
From: Ryan Dahl <ry@tinyclouds.org>
Date: Fri, 19 Mar 2010 02:24:11 -0700
Subject: [PATCH] [net2] inline write on empty write buffer for performance

---
 lib/net.js                       | 83 ++++++++++++++++++++++++++++++++++++++--
 test/simple/test-net-pingpong.js |  3 ++
 2 files changed, 83 insertions(+), 3 deletions(-)

diff --git a/lib/net.js b/lib/net.js
index ed74679..c6141a5 100644
--- a/lib/net.js
+++ b/lib/net.js
@@ -501,6 +501,83 @@ Stream.prototype.write = function (data, encoding) {
 
   if (!self.writable) throw new Error('Stream is not writable');
 
+  if (self._writeQueue && self._writeQueue.length) {
+    return self._writeQueued(data, encoding); // slow
+
+  } else {
+    // The most common case. There is no write queue. Just push the data
+    // directly to the socket.
+
+    var bytesWritten;
+    var buffer = data, off = 0, len = data.length;
+
+    if (typeof data == 'string') {
+      encoding = (encoding || 'utf8').toLowerCase();
+      var bytes = encoding == 'utf8' ? Buffer.utf8ByteLength(data) : data.length;
+
+      //debug('write string :' + JSON.stringify(data));
+
+      if (!recvBuffer) allocRecvBuffer();
+
+      if (recvBuffer.length - recvBuffer.used < bytes) {
+        // not enough room - go to slow case
+        return self._writeQueued(data, encoding);
+      }
+
+      var charsWritten;
+      if (encoding == 'utf8') {
+        recvBuffer.utf8Write(data, recvBuffer.used);
+      } else {
+        // ascii
+        recvBuffer.asciiWrite(data, recvBuffer.used);
+      }
+       
+      buffer = recvBuffer;
+      off = recvBuffer.used;
+      len = bytes;
+    }
+
+    //debug('write [fd, off, len] =' + JSON.stringify([self.fd, off, len]));
+
+    // Send the buffer.
+    try {
+      bytesWritten = write(self.fd, buffer, off, len);
+    } catch (e) {
+      self.forceClose(e);
+      return false;
+    }
+
+    //debug('wrote ' + bytesWritten);
+
+    // Note: if using the recvBuffer - we don't need to increase
+    // recvBuffer.used because it was all sent. Just reuse that space.
+
+    if (bytesWritten == len) return true;
+
+    //debug('write incomplete ' + bytesWritten + ' < ' + len);
+
+    if (buffer == data) {
+      data.sent = bytesWritten || 0;
+      data.used = data.length;
+    } else {
+      // string
+      recvBuffer.used += bytesWritten;
+      data = recvBuffer.slice(off+bytesWritten, off+len+bytesWritten);
+      data.sent = 0;
+      data.used = data.length;
+    }
+
+    //if (!self._writeQueue) initWriteStream(self);
+    self._writeQueue.push(data);
+    self._writeQueueSize += data.used;
+    return false;
+  }
+}
+
+Stream.prototype._writeQueued = function (data, encoding) {
+  //debug('_writeQueued');
+  var self = this;
+
   if (self.__writeQueueLast() == END_OF_FILE) {
     throw new Error('socket.close() called already; cannot write.');
   }
@@ -597,7 +674,7 @@ Stream.prototype.flush = function () {
     } else {
       b.sent += bytesWritten;
       self._writeQueueSize -= bytesWritten;
-      debug('bytes sent: ' + b.sent);
+      //debug('bytes sent: ' + b.sent);
     }
   }
   if (self._writeWatcher) self._writeWatcher.stop();
@@ -654,7 +731,7 @@ Stream.prototype.connect = function () {
 
   if (port >= 0) {
     self.fd = socket('tcp');
-    debug('new fd = ' + self.fd);
+    //debug('new fd = ' + self.fd);
     self.type = 'tcp';
     // TODO dns resolution on arguments[1]
     var port = arguments[0];
@@ -726,7 +803,7 @@ Stream.prototype.forceClose = function (exception) {
   // FIXME Bug when this.fd == 0
   if (this.fd) {
     close(this.fd);
-    debug('close ' + this.fd);
+    //debug('close ' + this.fd);
     this.fd = null;
     process.nextTick(function () {
       if (exception) self.emit('error', exception);
diff --git a/test/simple/test-net-pingpong.js b/test/simple/test-net-pingpong.js
index ad6410c..860b200 100644
--- a/test/simple/test-net-pingpong.js
+++ b/test/simple/test-net-pingpong.js
@@ -20,6 +20,7 @@ function pingPongTest (port, host) {
     socket.setNoDelay();
     socket.timeout = 0;
 
+    socket.setEncoding('utf8');
     socket.addListener("data", function (data) {
       puts("server got: " + data);
       assert.equal(true, socket.writable);
@@ -53,6 +54,7 @@ function pingPongTest (port, host) {
 
     var client = net.createConnection(port, host);
 
+    client.setEncoding('ascii');
     client.addListener("connect", function () {
       assert.equal(true, client.readable);
       assert.equal(true, client.writable);
@@ -106,4 +108,5 @@ pingPongTest("/tmp/pingpong.sock");
 
 process.addListener("exit", function () {
   assert.equal(4, tests_run);
+  puts('done');
 });
-- 
2.7.4