Deciding best connection to schedule requests on based on cwnd and idle time (Reopened after revert)

net/socket/client_socket_pool_base_unittest.cc

Index: net/socket/client_socket_pool_base_unittest.cc
===================================================================
--- net/socket/client_socket_pool_base_unittest.cc	(revision 90551)
+++ net/socket/client_socket_pool_base_unittest.cc	(working copy)
@@ -45,12 +45,14 @@
 
 class MockClientSocket : public StreamSocket {
  public:
-  MockClientSocket() : connected_(false), was_used_to_convey_data_(false) {}
+  MockClientSocket() : connected_(false), was_used_to_convey_data_(false),
+                       num_bytes_read_(0) {}
 
   // Socket methods:
   virtual int Read(
-      IOBuffer* /* buf */, int /* len */, CompletionCallback* /* callback */) {
-    return ERR_UNEXPECTED;
+      IOBuffer* /* buf */, int len, CompletionCallback* /* callback */) {
+    num_bytes_read_ += len;
+    return len;
   }
 
   virtual int Write(
@@ -86,13 +88,22 @@
 
   virtual void SetSubresourceSpeculation() {}
   virtual void SetOmniboxSpeculation() {}
-  virtual bool WasEverUsed() const { return was_used_to_convey_data_; }
+  virtual bool WasEverUsed() const {
+    return was_used_to_convey_data_ || num_bytes_read_ > 0;
+  }
   virtual bool UsingTCPFastOpen() const { return false; }
+  virtual int64 NumBytesRead() const { return num_bytes_read_; }
+  virtual base::TimeDelta GetConnectTimeMicros() const {
+    static const base::TimeDelta kDummyConnectTimeMicros =
+        base::TimeDelta::FromMicroseconds(10);
+    return kDummyConnectTimeMicros;  // Dummy value.
+  }
 
  private:
   bool connected_;
   BoundNetLog net_log_;
   bool was_used_to_convey_data_;
+  int num_bytes_read_;
 
   DISALLOW_COPY_AND_ASSIGN(MockClientSocket);
 };
@@ -604,6 +615,71 @@
   ClientSocketPoolTest test_base_;
 };
 
+TEST_F(ClientSocketPoolBaseTest, AssignIdleSocketToGroup_WarmestSocket) {
+  CreatePool(4, 4);
+  net::SetSocketReusePolicy(0);
+
+  EXPECT_EQ(OK, StartRequest("a", kDefaultPriority));
+  EXPECT_EQ(OK, StartRequest("a", kDefaultPriority));
+  EXPECT_EQ(OK, StartRequest("a", kDefaultPriority));
+  EXPECT_EQ(OK, StartRequest("a", kDefaultPriority));
+
+  std::map<int, StreamSocket*> sockets_;
+  for (size_t i = 0; i < test_base_.requests_size(); i++) {
+    TestSocketRequest* req = test_base_.request(i);
+    StreamSocket* s = req->handle()->socket();
+    MockClientSocket* sock = static_cast<MockClientSocket*>(s);
+    CHECK(sock);
+    sockets_[i] = sock;
+    sock->Read(NULL, 1024 - i, NULL);
+  }
+
+  ReleaseAllConnections(ClientSocketPoolTest::KEEP_ALIVE);
+
+  EXPECT_EQ(OK, StartRequest("a", kDefaultPriority));
+  TestSocketRequest* req = test_base_.request(test_base_.requests_size() - 1);
+
+  // First socket is warmest.
+  EXPECT_EQ(sockets_[0], req->handle()->socket());
+
+  // Test that NumBytes are as expected.
+  EXPECT_EQ(1024, sockets_[0]->NumBytesRead());
+  EXPECT_EQ(1023, sockets_[1]->NumBytesRead());
+  EXPECT_EQ(1022, sockets_[2]->NumBytesRead());
+  EXPECT_EQ(1021, sockets_[3]->NumBytesRead());
+
+  ReleaseAllConnections(ClientSocketPoolTest::NO_KEEP_ALIVE);
+}
+
+TEST_F(ClientSocketPoolBaseTest, AssignIdleSocketToGroup_LastAccessedSocket) {
+  CreatePool(4, 4);
+  net::SetSocketReusePolicy(2);
+
+  EXPECT_EQ(OK, StartRequest("a", kDefaultPriority));
+  EXPECT_EQ(OK, StartRequest("a", kDefaultPriority));
+  EXPECT_EQ(OK, StartRequest("a", kDefaultPriority));
+  EXPECT_EQ(OK, StartRequest("a", kDefaultPriority));
+
+  std::map<int, StreamSocket*> sockets_;
+  for (size_t i = 0; i < test_base_.requests_size(); i++) {
+    TestSocketRequest* req = test_base_.request(i);
+    StreamSocket* s = req->handle()->socket();
+    MockClientSocket* sock = static_cast<MockClientSocket*>(s);
+    CHECK(sock);
+    sockets_[i] = sock;
+    sock->Read(NULL, 1024 - i, NULL);
+  }
+
+  ReleaseAllConnections(ClientSocketPoolTest::KEEP_ALIVE);
+
+  EXPECT_EQ(OK, StartRequest("a", kDefaultPriority));
+  TestSocketRequest* req = test_base_.request(test_base_.requests_size() - 1);
+
+  // Last socket is most recently accessed.
+  EXPECT_EQ(sockets_[3], req->handle()->socket());
+  ReleaseAllConnections(ClientSocketPoolTest::NO_KEEP_ALIVE);
+}
+
 // Even though a timeout is specified, it doesn't time out on a synchronous
 // completion.
 TEST_F(ClientSocketPoolBaseTest, ConnectJob_NoTimeoutOnSynchronousCompletion) {