diff --git a/octavia_lib/api/drivers/driver_lib.py b/octavia_lib/api/drivers/driver_lib.py
index 99b6612..6894446 100644
--- a/octavia_lib/api/drivers/driver_lib.py
+++ b/octavia_lib/api/drivers/driver_lib.py
@@ -14,6 +14,7 @@
 
 import os
 import socket
+import sys
 import time
 
 from oslo_serialization import jsonutils
@@ -67,8 +68,12 @@ class DriverLibrary():
                 raise driver_exceptions.DriverAgentTimeout(
                     fault_string=('The driver agent did not respond in {} '
                                   'seconds.'.format(DRIVER_AGENT_TIMEOUT)))
-            # Give the CPU a break from polling
-            time.sleep(0.01)
+            # TODO(gthiemonge) remove time.sleep when py36 is no longer used:
+            # see note in # https://docs.python.org/3/library/socket.html#\
+            # socket.socket.settimeout
+            if sock.type & socket.SOCK_NONBLOCK:
+                # Give the CPU a break from polling
+                time.sleep(0.01)
         payload_size = int(size_str)
         mv_buffer = memoryview(bytearray(payload_size))
         next_offset = 0
@@ -81,8 +86,12 @@ class DriverLibrary():
                 raise driver_exceptions.DriverAgentTimeout(
                     fault_string=('The driver agent did not respond in {} '
                                   'seconds.'.format(DRIVER_AGENT_TIMEOUT)))
-            # Give the CPU a break from polling
-            time.sleep(0.01)
+            # TODO(gthiemonge) remove time.sleep when py36 is no longer used:
+            # see note in # https://docs.python.org/3/library/socket.html#\
+            # socket.socket.settimeout
+            if sock.type & socket.SOCK_NONBLOCK:
+                # Give the CPU a break from polling
+                time.sleep(0.01)
         return jsonutils.loads(mv_buffer.tobytes())
 
     def _send(self, socket_path, data):
@@ -94,7 +103,10 @@ class DriverLibrary():
             len_str = '{}\n'.format(len(json_data)).encode('utf-8')
             sock.send(len_str)
             sock.sendall(json_data)
+            start = time.time()
             response = self._recv(sock)
+            end = time.time()
+            sys.stderr.write("_recv in {} sec\n".format(end - start))
         finally:
             sock.close()
         return response
@@ -216,7 +228,10 @@ class DriverLibrary():
         :raises DriverError: An unexpected error occurred.
         :returns: A HealthMonitor object or None if not found.
         """
+        start = time.time()
         data = self._get_resource(constants.HEALTHMONITORS, healthmonitor_id)
+        end = time.time()
+        sys.stderr.write("got resource in {}\n".format(end - start))
         if data:
             return data_models.HealthMonitor.from_dict(data)
         return None