diff --git a/doc/conf.py b/doc/conf.py
index 3a8c5ac5155f..d6c124f39153 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -18,7 +18,7 @@
 
 # These 4 lines added to enable ReadTheDocs to work.
 import mock
-MOCK_MODULES = ["libraylib", "IPython", "numpy", "funcsigs", "subprocess32", "protobuf", "colorama", "graphviz", "cloudpickle", "ray.internal.graph_pb2"]
+MOCK_MODULES = ["numpy", "funcsigs", "colorama", "cloudpickle"]
 for mod_name in MOCK_MODULES:
   sys.modules[mod_name] = mock.Mock()
 
diff --git a/doc/install-on-macosx.md b/doc/install-on-macosx.md
index a45784e66699..f21cb4f3daa9 100644
--- a/doc/install-on-macosx.md
+++ b/doc/install-on-macosx.md
@@ -16,10 +16,9 @@ install [Anaconda](https://www.continuum.io/downloads).
 
 ```
 brew update
-brew install git cmake automake autoconf libtool boost graphviz
+brew install git cmake automake autoconf libtool boost
 sudo easy_install pip
-sudo pip install ipython --user
-sudo pip install numpy funcsigs subprocess32 protobuf colorama graphviz --ignore-installed six
+sudo pip install numpy funcsigs colorama --ignore-installed six
 sudo pip install --upgrade git+git://github.com/cloudpipe/cloudpickle.git@0d225a4695f1f65ae1cbb2e0bbc145e10167cce4  # We use the latest version of cloudpickle because it can serialize named tuples.
 ```
 
diff --git a/doc/install-on-ubuntu.md b/doc/install-on-ubuntu.md
index 8d832fb736f7..b9cfc3c2d29a 100644
--- a/doc/install-on-ubuntu.md
+++ b/doc/install-on-ubuntu.md
@@ -14,8 +14,8 @@ First install the dependencies. We currently do not support Python 3.
 
 ```
 sudo apt-get update
-sudo apt-get install -y git cmake build-essential autoconf curl libtool python-dev python-numpy python-pip libboost-all-dev unzip graphviz
-sudo pip install ipython funcsigs subprocess32 protobuf colorama graphviz
+sudo apt-get install -y git cmake build-essential autoconf curl libtool python-dev python-numpy python-pip libboost-all-dev unzip
+sudo pip install funcsigs colorama
 sudo pip install --upgrade git+git://github.com/cloudpipe/cloudpickle.git@0d225a4695f1f65ae1cbb2e0bbc145e10167cce4  # We use the latest version of cloudpickle because it can serialize named tuples.
 ```
 
diff --git a/install-dependencies.sh b/install-dependencies.sh
index 8c283e3efc41..0fcf5f28c5a7 100755
--- a/install-dependencies.sh
+++ b/install-dependencies.sh
@@ -30,15 +30,14 @@ fi
 if [[ $platform == "linux" ]]; then
   # These commands must be kept in sync with the installation instructions.
   sudo apt-get update
-  sudo apt-get install -y git cmake build-essential autoconf curl libtool python-dev python-numpy python-pip libboost-all-dev unzip graphviz
-  sudo pip install ipython funcsigs subprocess32 protobuf colorama graphviz redis
+  sudo apt-get install -y git cmake build-essential autoconf curl libtool python-dev python-numpy python-pip libboost-all-dev unzip
+  sudo pip install funcsigs colorama redis
   sudo pip install --upgrade git+git://github.com/cloudpipe/cloudpickle.git@0d225a4695f1f65ae1cbb2e0bbc145e10167cce4  # We use the latest version of cloudpickle because it can serialize named tuples.
 elif [[ $platform == "macosx" ]]; then
   # These commands must be kept in sync with the installation instructions.
-  brew install git cmake automake autoconf libtool boost graphviz
+  brew install git cmake automake autoconf libtool boost
   sudo easy_install pip
-  sudo pip install ipython --user
-  sudo pip install numpy funcsigs subprocess32 protobuf colorama graphviz redis --ignore-installed six
+  sudo pip install numpy funcsigs colorama redis --ignore-installed six
   sudo pip install --upgrade git+git://github.com/cloudpipe/cloudpickle.git@0d225a4695f1f65ae1cbb2e0bbc145e10167cce4  # We use the latest version of cloudpickle because it can serialize named tuples.
 fi
 
diff --git a/lib/python/ray/services.py b/lib/python/ray/services.py
index 75a9b7a6dd54..b6c08da2977a 100644
--- a/lib/python/ray/services.py
+++ b/lib/python/ray/services.py
@@ -9,6 +9,7 @@
 
 # Ray modules
 import config
+import plasma
 
 # all_processes is a list of the scheduler, object store, and worker processes
 # that have been started by this services module if Ray is being used in local
@@ -80,15 +81,8 @@ def start_objstore(node_ip_address, redis_address, cleanup):
   store_name = "/tmp/ray_plasma_store{}".format(random_name())
   p1 = subprocess.Popen([plasma_store_executable, "-s", store_name])
 
-  plasma_manager_executable = os.path.join(os.path.abspath(os.path.dirname(__file__)), "../plasma/build/plasma_manager")
   manager_name = "/tmp/ray_plasma_manager{}".format(random_name())
-  manager_port = new_port()
-  p2 = subprocess.Popen([plasma_manager_executable,
-                         "-s", store_name,
-                         "-m", manager_name,
-                         "-h", node_ip_address,
-                         "-p", str(manager_port),
-                         "-r", redis_address])
+  p2, manager_port = plasma.start_plasma_manager(store_name, manager_name, redis_address)
 
   if cleanup:
     all_processes.append(p1)
diff --git a/lib/python/ray/worker.py b/lib/python/ray/worker.py
index a3370cf9e801..5a0b33d32cca 100644
--- a/lib/python/ray/worker.py
+++ b/lib/python/ray/worker.py
@@ -1086,8 +1086,7 @@ def process_task(task): # wrapping these lines in a function should cause the lo
       # We record the traceback and notify the scheduler.
       traceback_str = format_error_message(traceback.format_exc())
       error_key = "ReusableVariableReinitializeError:{}".format(random_string())
-      worker.redis_client.hmset(error_key, {"task_instance_id": "NOTIMPLEMENTED",
-                                            "task_id": "NOTIMPLEMENTED",
+      worker.redis_client.hmset(error_key, {"task_id": "NOTIMPLEMENTED",
                                             "function_id": function_id.id(),
                                             "function_name": function_name,
                                             "message": traceback_str})
@@ -1151,7 +1150,6 @@ def _export_reusable_variable(name, reusable, worker=global_worker):
   """
   if _mode(worker) not in [SCRIPT_MODE, SILENT_MODE]:
     raise Exception("_export_reusable_variable can only be called on a driver.")
-
   reusable_variable_id = name
   key = "ReusableVariables:{}".format(reusable_variable_id)
   worker.redis_client.hmset(key, {"name": name,
@@ -1161,11 +1159,10 @@ def _export_reusable_variable(name, reusable, worker=global_worker):
   worker.driver_export_counter += 1
 
 def export_remote_function(function_id, func_name, func, num_return_vals, worker=global_worker):
+  if _mode(worker) not in [SCRIPT_MODE, SILENT_MODE]:
+    raise Exception("export_remote_function can only be called on a driver.")
   key = "RemoteFunction:{}".format(function_id.id())
-
   worker.num_return_vals[function_id.id()] = num_return_vals
-
-
   pickled_func = pickling.dumps(func)
   worker.redis_client.hmset(key, {"function_id": function_id.id(),
                                   "name": func_name,
diff --git a/src/plasma/lib/python/plasma.py b/src/plasma/lib/python/plasma.py
index a869d136a5a7..c838cb247a63 100644
--- a/src/plasma/lib/python/plasma.py
+++ b/src/plasma/lib/python/plasma.py
@@ -1,6 +1,8 @@
+import ctypes
 import os
+import random
 import socket
-import ctypes
+import subprocess
 import time
 
 Addr = ctypes.c_ubyte * 4
@@ -287,3 +289,48 @@ def get_next_notification(self):
         assert len(message_data) == PLASMA_ID_SIZE
         break
     return message_data
+
+def start_plasma_manager(store_name, manager_name, redis_address, num_retries=5, use_valgrind=False):
+  """Start a plasma manager and return the ports it listens on.
+
+  Args:
+    store_name (str): The name of the plasma store socket.
+    manager_name (str): The name of the plasma manager socket.
+    redis_address (str): The address of the Redis server.
+    use_valgrind (bool): True if the Plasma manager should be started inside of
+      valgrind and False otherwise.
+
+  Returns:
+    The process ID of the Plasma manager and the port that the manager is
+      listening on.
+
+  Raises:
+    Exception: An exception is raised if the manager could not be properly
+      started.
+  """
+  plasma_manager_executable = os.path.join(os.path.abspath(os.path.dirname(__file__)), "../../build/plasma_manager")
+  port = None
+  process = None
+  counter = 0
+  while counter < num_retries:
+    if counter > 0:
+      print("Plasma manager failed to start, retrying now.")
+    port = random.randint(10000, 65535)
+    command = [plasma_manager_executable,
+               "-s", store_name,
+               "-m", manager_name,
+               "-h", "127.0.0.1",
+               "-p", str(port),
+               "-r", redis_address]
+    if use_valgrind:
+      process = subprocess.Popen(["valgrind", "--track-origins=yes", "--leak-check=full", "--show-leak-kinds=all", "--error-exitcode=1"] + command)
+    else:
+      process = subprocess.Popen(command)
+    # This sleep is critical. If the plasma_manager fails to start because the
+    # port is already in use, then we need it to fail within 0.1 seconds.
+    time.sleep(0.1)
+    # See if the process has terminated
+    if process.poll() == None:
+      return process, port
+    counter += 1
+  raise Exception("Couldn't start plasma manager.")
diff --git a/src/plasma/test/test.py b/src/plasma/test/test.py
index 9613126edf3c..caeaa79fe911 100644
--- a/src/plasma/test/test.py
+++ b/src/plasma/test/test.py
@@ -53,32 +53,6 @@ def assert_get_object_equal(unit_test, client1, client2, object_id, memory_buffe
   unit_test.assertEqual(client1.get_metadata(object_id)[:],
                         client2.get_metadata(object_id)[:])
 
-def start_plasma_manager(store_name, host_name, redis_port, use_valgrind=False):
-  """Start a plasma manager and return the ports it listens on."""
-  plasma_manager_executable = os.path.join(os.path.abspath(os.path.dirname(__file__)), "../build/plasma_manager")
-  num_retries = 5
-  port = None
-  process = None
-  while num_retries >= 0:
-    port = random.randint(10000, 50000)
-    command = [plasma_manager_executable,
-               "-s", store_name,
-               "-m", host_name,
-               "-h", "127.0.0.1",
-               "-p", str(port),
-               "-r", "{addr}:{port}".format(addr="127.0.0.1", port=redis_port)]
-    print("Try to start plasma manager on port " + str(port))
-    if use_valgrind:
-      process = subprocess.Popen(["valgrind", "--track-origins=yes", "--leak-check=full", "--show-leak-kinds=all", "--error-exitcode=1"] + command)
-    else:
-      process = subprocess.Popen(command)
-    time.sleep(0.1)
-    # See if the process has terminated
-    if process.poll() == None:
-      return process, port
-    num_retries = num_retries - 1
-  raise Exception("Couldn't start plasma manager")
-
 # Check if the redis-server binary is present.
 redis_path = os.path.join(os.path.abspath(os.path.dirname(__file__)), "../../common/thirdparty/redis-3.2.3/src/redis-server")
 if not os.path.exists(redis_path):
@@ -266,8 +240,9 @@ def setUp(self):
     time.sleep(0.1)
 
     # Start two PlasmaManagers.
-    self.p4, self.port1 = start_plasma_manager(store_name1, manager_name1, redis_port, USE_VALGRIND)
-    self.p5, self.port2 = start_plasma_manager(store_name2, manager_name2, redis_port, USE_VALGRIND)
+    redis_address = "{}:{}".format("127.0.0.1", redis_port)
+    self.p4, self.port1 = plasma.start_plasma_manager(store_name1, manager_name1, redis_address, use_valgrind=USE_VALGRIND)
+    self.p5, self.port2 = plasma.start_plasma_manager(store_name2, manager_name2, redis_address, use_valgrind=USE_VALGRIND)
 
     # Connect two PlasmaClients.
     self.client1 = plasma.PlasmaClient(store_name1, manager_name1)