bpo-41273: Double proactor read transport buffer size

By doubling the read buffer size we get better performance.

Author: tontinton

Lib/asyncio/proactor_events.py

@@ -179,7 +179,7 @@ class _ProactorReadPipeTransport(_ProactorBasePipeTransport,
     """Transport for read pipes."""
 
     def __init__(self, loop, sock, protocol, waiter=None,
-                 extra=None, server=None, buffer_size=32768):
+                 extra=None, server=None, buffer_size=65536):
         self._pending_data_length = -1
         self._paused = True
         super().__init__(loop, sock, protocol, waiter, extra, server)

Lib/test/test_asyncio/test_proactor_events.py

@@ -40,7 +40,7 @@ def setUp(self):
         self.loop._proactor = self.proactor
         self.protocol = test_utils.make_test_protocol(asyncio.Protocol)
         self.sock = mock.Mock(socket.socket)
-        self.buffer_size = 32768
+        self.buffer_size = 65536
 
     def socket_transport(self, waiter=None):
         transport = _ProactorSocketTransport(self.loop, self.sock,