UDP: Windows implementation using non-blocking IO

net/udp/udp_socket_perftest.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/basictypes.h"
+#include "base/bind.h"
+#include "base/memory/weak_ptr.h"
+#include "base/run_loop.h"
+#include "base/test/perf_time_logger.h"
+#include "net/base/io_buffer.h"
+#include "net/base/ip_endpoint.h"
+#include "net/base/net_errors.h"
+#include "net/base/net_log_unittest.h"
+#include "net/base/net_util.h"
+#include "net/base/test_completion_callback.h"
+#include "net/test/net_test_suite.h"
+#include "net/udp/udp_client_socket.h"
+#include "net/udp/udp_server_socket.h"
+#include "net/udp/udp_socket.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "testing/platform_test.h"
+
+namespace net {

[rvargas (doing something else), 2015/01/23 03:05:35]

Please take the test out of the net namespace. The reason is that I (as a random
reader) don't want to have to figure out where each thing is coming from, and
having that spelled out in the code as I read it is useful.

[Alpha Left Google, 2015/01/23 03:52:22]

Done.

+
+namespace {
+
+class UDPSocketPerfTest : public PlatformTest {
+ public:
+  UDPSocketPerfTest()
+      : buffer_(new IOBufferWithSize(kPacketSize)), weak_factory_(this) {}
+
+  void DoneWritePacketsToSocket(UDPClientSocket* socket,
+                                int num_of_packets,
+                                base::Closure done_callback,
+                                int error) {
+    WritePacketsToSocket(socket, num_of_packets, done_callback);
+  }
+
+  // Send |num_of_packets| to |socket|. Invoke |done_callback| when done.
+  void WritePacketsToSocket(UDPClientSocket* socket,

[rvargas (doing something else), 2015/01/23 03:05:35]

This class is too long to use inline definitions.

[Alpha Left Google, 2015/01/23 03:52:22]

Defined it out of class.

+                            int num_of_packets,
+                            base::Closure done_callback) {
+    std::string msg(kPacketSize, 'G');
+    scoped_refptr<StringIOBuffer> io_buffer(new StringIOBuffer(msg));

[rvargas (doing something else), 2015/01/23 03:05:35]

I know this is just a test, but having a memcpy here just so that the previous
line can be done with a std template instead of memset seems like setting a bad
example. 

[Alpha Left Google, 2015/01/23 03:52:22]

Done.

+
+    while (num_of_packets) {

[rvargas (doing something else), 2015/01/23 03:05:34]

for ?

[Alpha Left Google, 2015/01/23 03:52:22]

I need a counter to track how many packets are sent. If i use a for i need a
separate counter. This seems to be cleaner to me.

+      int rv =
+          socket->Write(io_buffer.get(), io_buffer->size(),
+                        base::Bind(&UDPSocketPerfTest::DoneWritePacketsToSocket,
+                                   weak_factory_.GetWeakPtr(), socket,
+                                   num_of_packets - 1, done_callback));
+      if (rv == ERR_IO_PENDING)
+        break;
+      --num_of_packets;
+    }
+    if (!num_of_packets) {
+      done_callback.Run();
+      return;
+    }
+  }
+
+  // Creates and address from an ip/port and returns it in |address|.
+  void CreateUDPAddress(std::string ip_str, uint16 port, IPEndPoint* address) {
+    IPAddressNumber ip_number;
+    bool rv = ParseIPLiteralToNumber(ip_str, &ip_number);
+    if (!rv)
+      return;
+    *address = IPEndPoint(ip_number, port);
+  }
+
+  // Use non-blocking IO if |use_nonblocking_io| is true. This variable only
+  // has effect on Windows.
+  void WriteBenchmark(bool use_nonblocking_io) {
+    const uint16 kPort = 9999;
+    std::string simple_message("hello world!");
+
+    // Setup the server to listen.
+    IPEndPoint bind_address;
+    CreateUDPAddress("127.0.0.1", kPort, &bind_address);
+    CapturingNetLog server_log;
+    scoped_ptr<UDPServerSocket> server(
+        new UDPServerSocket(&server_log, NetLog::Source()));
+#if defined(OS_WIN)
+    if (use_nonblocking_io)
+      server->UseNonBlockingIO();
+#endif
+    server->AllowAddressReuse();

[rvargas (doing something else), 2015/01/23 03:05:35]

This generates unreliable behavior on Windows.

[Alpha Left Google, 2015/01/23 03:52:22]

Done.

+    int rv = server->Listen(bind_address);
+    ASSERT_EQ(OK, rv);
+
+    // Setup the client.
+    IPEndPoint server_address;
+    CreateUDPAddress("127.0.0.1", kPort, &server_address);
+    CapturingNetLog client_log;
+    scoped_ptr<UDPClientSocket> client(
+        new UDPClientSocket(DatagramSocket::DEFAULT_BIND, RandIntCallback(),
+                            &client_log, NetLog::Source()));
+#if defined(OS_WIN)
+    if (use_nonblocking_io)
+      client->UseNonBlockingIO();
+#endif
+    rv = client->Connect(server_address);
+    EXPECT_EQ(OK, rv);
+
+    base::RunLoop run_loop;
+    base::TimeTicks start_ticks = base::TimeTicks::Now();
+    int packets = 100000;
+    client->SetSendBufferSize(1024 * 128);
+    WritePacketsToSocket(client.get(), packets, run_loop.QuitClosure());
+    run_loop.Run();
+
+    double elapsed = (base::TimeTicks::Now() - start_ticks).InSecondsF();
+    LOG(INFO) << "Write speed: " << packets / 1024 / elapsed << " MB/s";
+    server.reset();

[rvargas (doing something else), 2015/01/23 03:05:35]

Don't really need these, do you?

[Alpha Left Google, 2015/01/23 03:52:22]

Done.

+    client.reset();
+  }
+
+ protected:
+  static const int kPacketSize = 1024;
+  scoped_refptr<IOBufferWithSize> buffer_;
+  base::WeakPtrFactory<UDPSocketPerfTest> weak_factory_;
+};
+
+TEST_F(UDPSocketPerfTest, Write) {
+  base::PerfTimeLogger timer("UDP_socket_write");
+  WriteBenchmark(false);
+}
+
+#if defined(OS_WIN)
+TEST_F(UDPSocketPerfTest, WriteNonBlocking) {
+  base::PerfTimeLogger timer("UDP_socket_write_nonblocking");
+  WriteBenchmark(true);
+}
+#endif
+
+}  // namespace
+
+}  // namespace net