diff --git a/python/ray/_raylet.pyx b/python/ray/_raylet.pyx
index f70e64ea4..a2a7d1560 100644
--- a/python/ray/_raylet.pyx
+++ b/python/ray/_raylet.pyx
@@ -895,7 +895,7 @@ cdef class CoreWorker:
             c_vector[CTaskArg] args_vector
             c_vector[CObjectID] return_ids
 
-        with profiling.profile("submit_task"):
+        with self.profile_event("submit_task"):
             prepare_resources(resources, &c_resources)
             task_options = CTaskOptions(num_return_vals, c_resources)
             ray_function = CRayFunction(
@@ -954,7 +954,7 @@ cdef class CoreWorker:
             c_vector[CTaskArg] args_vector
             c_vector[CObjectID] return_ids
 
-        with profiling.profile("submit_task"):
+        with self.profile_event("submit_task"):
             prepare_resources(resources, &c_resources)
             task_options = CTaskOptions(num_return_vals, c_resources)
             ray_function = CRayFunction(
@@ -991,7 +991,7 @@ cdef class CoreWorker:
 
         return resources_dict
 
-    def profile_event(self, event_type, dict extra_data):
+    def profile_event(self, event_type, object extra_data=None):
         cdef:
             c_string c_event_type = event_type.encode("ascii")
 
diff --git a/python/ray/actor.py b/python/ray/actor.py
index f774b99c9..203b83ffc 100644
--- a/python/ray/actor.py
+++ b/python/ray/actor.py
@@ -16,7 +16,7 @@ import ray.ray_constants as ray_constants
 import ray._raylet
 import ray.signature as signature
 import ray.worker
-from ray import ActorID, ActorClassID, profiling
+from ray import ActorID, ActorClassID
 
 logger = logging.getLogger(__name__)
 
@@ -468,6 +468,12 @@ class ActorHandle(object):
         self._ray_class_name = class_name
         self._ray_actor_method_cpus = actor_method_cpus
         self._ray_session_and_job = session_and_job
+        self._ray_function_descriptor_lists = {
+            method_name: FunctionDescriptor(
+                self._ray_module_name, method_name,
+                self._ray_class_name).get_function_descriptor_list()
+            for method_name in self._ray_method_signatures.keys()
+        }
 
     def _actor_method_call(self,
                            method_name,
@@ -500,20 +506,15 @@ class ActorHandle(object):
         kwargs = kwargs or {}
 
         list_args = signature.flatten_args(function_signature, args, kwargs)
-        function_descriptor = FunctionDescriptor(
-            self._ray_module_name, method_name, self._ray_class_name)
-        with profiling.profile("submit_task"):
-            if worker.mode == ray.LOCAL_MODE:
-                function = getattr(worker.actors[self._actor_id], method_name)
-                object_ids = worker.local_mode_manager.execute(
-                    function, function_descriptor, args, kwargs,
-                    num_return_vals)
-            else:
-                object_ids = worker.core_worker.submit_actor_task(
-                    self._ray_actor_id,
-                    function_descriptor.get_function_descriptor_list(),
-                    list_args, num_return_vals,
-                    {"CPU": self._ray_actor_method_cpus})
+        if worker.mode == ray.LOCAL_MODE:
+            function = getattr(worker.actors[self._actor_id], method_name)
+            object_ids = worker.local_mode_manager.execute(
+                function, method_name, args, kwargs, num_return_vals)
+        else:
+            object_ids = worker.core_worker.submit_actor_task(
+                self._ray_actor_id,
+                self._ray_function_descriptor_lists[method_name], list_args,
+                num_return_vals, {"CPU": self._ray_actor_method_cpus})
 
         if len(object_ids) == 1:
             object_ids = object_ids[0]
diff --git a/python/ray/includes/libcoreworker.pxi b/python/ray/includes/libcoreworker.pxi
index 3060a2788..8e5a4d92b 100644
--- a/python/ray/includes/libcoreworker.pxi
+++ b/python/ray/includes/libcoreworker.pxi
@@ -9,10 +9,10 @@ cdef class ProfileEvent:
     """Cython wrapper class of C++ `ray::worker::ProfileEvent`."""
     cdef:
         unique_ptr[CProfileEvent] inner
-        dict extra_data
+        object extra_data
 
     @staticmethod
-    cdef make(unique_ptr[CProfileEvent] event, dict extra_data):
+    cdef make(unique_ptr[CProfileEvent] event, object extra_data):
         cdef ProfileEvent self = ProfileEvent.__new__(ProfileEvent)
         self.inner = move(event)
         self.extra_data = extra_data
@@ -25,7 +25,7 @@ cdef class ProfileEvent:
         pass
 
     def __exit__(self, type, value, tb):
-        extra_data = {}
+        extra_data = None
         if type is not None:
             extra_data = {
                 "type": str(type),
@@ -35,7 +35,7 @@ cdef class ProfileEvent:
         elif self.extra_data is not None:
             extra_data = self.extra_data
 
-        self.inner.get().SetExtraData(json.dumps(extra_data).encode("ascii"))
+        self.inner.get().SetExtraData(json.dumps(extra_data).encode("ascii") if extra_data else b"{}")
 
         # Deleting the CProfileEvent will add it to a queue to be pushed to
         # the driver.
diff --git a/python/ray/local_mode_manager.py b/python/ray/local_mode_manager.py
index d79a0113c..3d9d70a85 100644
--- a/python/ray/local_mode_manager.py
+++ b/python/ray/local_mode_manager.py
@@ -29,8 +29,7 @@ class LocalModeManager(object):
     def __init__(self):
         """Initialize a LocalModeManager."""
 
-    def execute(self, function, function_descriptor, args, kwargs,
-                num_return_vals):
+    def execute(self, function, function_name, args, kwargs, num_return_vals):
         """Synchronously executes a "remote" function or actor method.
 
         Stores results directly in the generated and returned
@@ -40,7 +39,7 @@ class LocalModeManager(object):
 
         Args:
             function: The function to execute.
-            function_descriptor: Metadata about the function.
+            function_name: Name of the function to execute.
             args: Arguments to the function. These will not be modified by
                 the function execution.
             kwargs: Keyword arguments to the function.
@@ -61,7 +60,6 @@ class LocalModeManager(object):
                 for object_id, result in zip(object_ids, results):
                     object_id.value = result
         except Exception as e:
-            function_name = function_descriptor.function_name
             backtrace = format_error_message(traceback.format_exc())
             task_error = RayTaskError(function_name, backtrace, e.__class__)
             for object_id in object_ids:
diff --git a/src/ray/core_worker/profiling.cc b/src/ray/core_worker/profiling.cc
index 847d55d01..0ce704d3b 100644
--- a/src/ray/core_worker/profiling.cc
+++ b/src/ray/core_worker/profiling.cc
@@ -10,7 +10,7 @@ ProfileEvent::ProfileEvent(const std::shared_ptr<Profiler> profiler,
                            const std::string &event_type)
     : profiler_(profiler) {
   rpc_event_.set_event_type(event_type);
-  rpc_event_.set_start_time(current_sys_time_seconds());
+  rpc_event_.set_start_time(absl::GetCurrentTimeNanos() / 1e9);
 }
 
 Profiler::Profiler(WorkerContext &worker_context, const std::string &node_ip_address,
@@ -19,6 +19,7 @@ Profiler::Profiler(WorkerContext &worker_context, const std::string &node_ip_add
     : io_service_(io_service),
       timer_(io_service_, boost::asio::chrono::seconds(1)),
       gcs_client_(gcs_client) {
+  absl::MutexLock l(&mu_);
   rpc_profile_data_.set_component_type(WorkerTypeString(worker_context.GetWorkerType()));
   rpc_profile_data_.set_component_id(worker_context.GetWorkerID().Binary());
   rpc_profile_data_.set_node_ip_address(node_ip_address);
@@ -26,12 +27,12 @@ Profiler::Profiler(WorkerContext &worker_context, const std::string &node_ip_add
 }
 
 void Profiler::AddEvent(const rpc::ProfileTableData::ProfileEvent &event) {
-  io_service_.post([this, event]() -> void {
-    rpc_profile_data_.add_profile_events()->CopyFrom(event);
-  });
+  absl::MutexLock l(&mu_);
+  rpc_profile_data_.add_profile_events()->CopyFrom(event);
 }
 
 void Profiler::FlushEvents() {
+  absl::MutexLock l(&mu_);
   if (rpc_profile_data_.profile_events_size() != 0) {
     // TODO(edoakes): this should be migrated to use the new GCS client interface
     // instead of the raw table interface once it's ready.
diff --git a/src/ray/core_worker/profiling.h b/src/ray/core_worker/profiling.h
index 8be39ae0f..2d745a6b1 100644
--- a/src/ray/core_worker/profiling.h
+++ b/src/ray/core_worker/profiling.h
@@ -1,9 +1,11 @@
 #ifndef RAY_CORE_WORKER_PROFILING_H
 #define RAY_CORE_WORKER_PROFILING_H
 
+#include "absl/synchronization/mutex.h"
+#include "absl/time/clock.h"
+
 #include "ray/core_worker/context.h"
 #include "ray/gcs/redis_gcs_client.h"
-#include "ray/util/util.h"
 
 namespace ray {
 
@@ -30,9 +32,11 @@ class Profiler {
 
   // RPC message containing profiling data. Holds the queue of profile events
   // until they are flushed.
-  rpc::ProfileTableData rpc_profile_data_;
+  rpc::ProfileTableData rpc_profile_data_ GUARDED_BY(mu_);
 
   std::unique_ptr<gcs::RedisGcsClient> &gcs_client_;
+
+  absl::Mutex mu_;
 };
 
 class ProfileEvent {
@@ -40,7 +44,7 @@ class ProfileEvent {
   ProfileEvent(const std::shared_ptr<Profiler> profiler, const std::string &event_type);
 
   ~ProfileEvent() {
-    rpc_event_.set_end_time(current_sys_time_seconds());
+    rpc_event_.set_end_time(absl::GetCurrentTimeNanos() / 1e9);
     profiler_->AddEvent(rpc_event_);
   }
 
diff --git a/src/ray/gcs/redis_context.cc b/src/ray/gcs/redis_context.cc
index 45ba6cdd7..b805a6322 100644
--- a/src/ray/gcs/redis_context.cc
+++ b/src/ray/gcs/redis_context.cc
@@ -27,7 +27,7 @@ void ProcessCallback(int64_t callback_index,
   auto callback_item = ray::gcs::RedisCallbackManager::instance().get(callback_index);
   if (!callback_item.is_subscription) {
     // Record the redis latency for non-subscription redis operations.
-    auto end_time = current_sys_time_us();
+    auto end_time = absl::GetCurrentTimeNanos() / 1000;
     ray::stats::RedisLatency().Record(end_time - callback_item.start_time);
   }
   // Invoke the callback.
@@ -134,7 +134,7 @@ void GlobalRedisCallback(void *c, void *r, void *privdata) {
 }
 
 int64_t RedisCallbackManager::add(const RedisCallback &function, bool is_subscription) {
-  auto start_time = current_sys_time_us();
+  auto start_time = absl::GetCurrentTimeNanos() / 1000;
 
   std::lock_guard<std::mutex> lock(mutex_);
   callback_items_.emplace(num_callbacks_,
diff --git a/src/ray/gcs/tables.cc b/src/ray/gcs/tables.cc
index dc003a76a..cc7399d01 100644
--- a/src/ray/gcs/tables.cc
+++ b/src/ray/gcs/tables.cc
@@ -1,10 +1,11 @@
 #include "ray/gcs/tables.h"
 
+#include "absl/time/clock.h"
+
 #include "ray/common/common_protocol.h"
 #include "ray/common/grpc_util.h"
 #include "ray/common/ray_config.h"
 #include "ray/gcs/redis_gcs_client.h"
-#include "ray/util/util.h"
 
 namespace {
 
@@ -713,7 +714,7 @@ Status ActorCheckpointIdTable::AddCheckpointId(const JobID &job_id,
                              const ActorCheckpointIdData &data) {
     std::shared_ptr<ActorCheckpointIdData> copy =
         std::make_shared<ActorCheckpointIdData>(data);
-    copy->add_timestamps(current_sys_time_ms());
+    copy->add_timestamps(absl::GetCurrentTimeNanos() / 1000000);
     copy->add_checkpoint_ids(checkpoint_id.Binary());
     auto num_to_keep = RayConfig::instance().num_actor_checkpoints_to_keep();
     while (copy->timestamps().size() > num_to_keep) {
@@ -730,7 +731,7 @@ Status ActorCheckpointIdTable::AddCheckpointId(const JobID &job_id,
     std::shared_ptr<ActorCheckpointIdData> data =
         std::make_shared<ActorCheckpointIdData>();
     data->set_actor_id(id.Binary());
-    data->add_timestamps(current_sys_time_ms());
+    data->add_timestamps(absl::GetCurrentTimeNanos() / 1000000);
     *data->add_checkpoint_ids() = checkpoint_id.Binary();
     RAY_CHECK_OK(Add(job_id, actor_id, data, nullptr));
   };
diff --git a/src/ray/object_manager/object_manager.cc b/src/ray/object_manager/object_manager.cc
index 84eaaf250..9f94f1242 100644
--- a/src/ray/object_manager/object_manager.cc
+++ b/src/ray/object_manager/object_manager.cc
@@ -369,9 +369,9 @@ void ObjectManager::Push(const ObjectID &object_id, const ClientID &client_id) {
     // We haven't pushed this specific object to this specific object manager
     // yet (or if we have then the object must have been evicted and recreated
     // locally).
-    recent_pushes[client_id] = current_sys_time_ms();
+    recent_pushes[client_id] = absl::GetCurrentTimeNanos() / 1000000;
   } else {
-    int64_t current_time = current_sys_time_ms();
+    int64_t current_time = absl::GetCurrentTimeNanos() / 1000000;
     if (current_time - it->second <=
         RayConfig::instance().object_manager_repeated_push_delay_ms()) {
       // We pushed this object to the object manager recently, so don't do it
@@ -419,7 +419,7 @@ ray::Status ObjectManager::SendObjectChunk(
     const UniqueID &push_id, const ObjectID &object_id, const ClientID &client_id,
     uint64_t data_size, uint64_t metadata_size, uint64_t chunk_index,
     std::shared_ptr<rpc::ObjectManagerClient> rpc_client) {
-  double start_time = current_sys_time_seconds();
+  double start_time = absl::GetCurrentTimeNanos() / 1e9;
   rpc::PushRequest push_request;
   // Set request header
   push_request.set_push_id(push_id.Binary());
@@ -459,7 +459,7 @@ ray::Status ObjectManager::SendObjectChunk(
                        << " failed due to" << status.message()
                        << ", chunk index: " << chunk_index;
     }
-    double end_time = current_sys_time_seconds();
+    double end_time = absl::GetCurrentTimeNanos() / 1e9;
     HandleSendFinished(object_id, client_id, chunk_index, start_time, end_time, status);
   };
   rpc_client->Push(push_request, callback);
@@ -677,10 +677,10 @@ void ObjectManager::HandlePushRequest(const rpc::PushRequest &request,
   uint64_t data_size = request.data_size();
   const std::string &data = request.data();
 
-  double start_time = current_sys_time_seconds();
+  double start_time = absl::GetCurrentTimeNanos() / 1e9;
   auto status = ReceiveObjectChunk(client_id, object_id, data_size, metadata_size,
                                    chunk_index, data);
-  double end_time = current_sys_time_seconds();
+  double end_time = absl::GetCurrentTimeNanos() / 1e9;
 
   HandleReceiveFinished(object_id, client_id, chunk_index, start_time, end_time, status);
   send_reply_callback(status, nullptr, nullptr);
@@ -722,7 +722,7 @@ void ObjectManager::HandlePullRequest(const rpc::PullRequest &request,
 
   rpc::ProfileTableData::ProfileEvent profile_event;
   profile_event.set_event_type("receive_pull_request");
-  profile_event.set_start_time(current_sys_time_seconds());
+  profile_event.set_start_time(absl::GetCurrentTimeNanos() / 1e9);
   profile_event.set_end_time(profile_event.start_time());
   profile_event.set_extra_data("[\"" + object_id.Hex() + "\",\"" + client_id.Hex() +
                                "\"]");
diff --git a/src/ray/object_manager/object_manager.h b/src/ray/object_manager/object_manager.h
index 00d5d9eef..47f88bc6b 100644
--- a/src/ray/object_manager/object_manager.h
+++ b/src/ray/object_manager/object_manager.h
@@ -14,6 +14,7 @@
 #include <boost/asio/error.hpp>
 #include <boost/bind.hpp>
 
+#include "absl/time/clock.h"
 #include "plasma/client.h"
 
 #include "ray/common/id.h"
diff --git a/src/ray/raylet/reconstruction_policy.h b/src/ray/raylet/reconstruction_policy.h
index a44819dca..dd9d23cb5 100644
--- a/src/ray/raylet/reconstruction_policy.h
+++ b/src/ray/raylet/reconstruction_policy.h
@@ -9,7 +9,6 @@
 
 #include "ray/common/id.h"
 #include "ray/gcs/tables.h"
-#include "ray/util/util.h"
 
 #include "ray/object_manager/object_directory.h"
 
diff --git a/src/ray/raylet/reconstruction_policy_test.cc b/src/ray/raylet/reconstruction_policy_test.cc
index 9a8ee6759..4e4c2801b 100644
--- a/src/ray/raylet/reconstruction_policy_test.cc
+++ b/src/ray/raylet/reconstruction_policy_test.cc
@@ -1,5 +1,6 @@
 #include <list>
 
+#include "absl/time/clock.h"
 #include "gmock/gmock.h"
 #include "gtest/gtest.h"
 
@@ -338,7 +339,7 @@ TEST_F(ReconstructionPolicyTest, TestReconstructionSuppressed) {
   // Acquire the task lease for a period longer than the test period.
   auto task_lease_data = std::make_shared<TaskLeaseData>();
   task_lease_data->set_node_manager_id(ClientID::FromRandom().Binary());
-  task_lease_data->set_acquired_at(current_sys_time_ms());
+  task_lease_data->set_acquired_at(absl::GetCurrentTimeNanos() / 1000000);
   task_lease_data->set_timeout(2 * test_period);
   mock_gcs_.Add(JobID::Nil(), task_id, task_lease_data);
 
@@ -366,7 +367,7 @@ TEST_F(ReconstructionPolicyTest, TestReconstructionContinuallySuppressed) {
   SetPeriodicTimer(reconstruction_timeout_ms_ / 2, [this, task_id]() {
     auto task_lease_data = std::make_shared<TaskLeaseData>();
     task_lease_data->set_node_manager_id(ClientID::FromRandom().Binary());
-    task_lease_data->set_acquired_at(current_sys_time_ms());
+    task_lease_data->set_acquired_at(absl::GetCurrentTimeNanos() / 1000000);
     task_lease_data->set_timeout(reconstruction_timeout_ms_);
     mock_gcs_.Add(JobID::Nil(), task_id, task_lease_data);
   });
diff --git a/src/ray/raylet/task_dependency_manager.cc b/src/ray/raylet/task_dependency_manager.cc
index ab52fe388..83137ef15 100644
--- a/src/ray/raylet/task_dependency_manager.cc
+++ b/src/ray/raylet/task_dependency_manager.cc
@@ -1,5 +1,7 @@
 #include "task_dependency_manager.h"
 
+#include "absl/time/clock.h"
+
 #include "ray/stats/stats.h"
 
 namespace ray {
@@ -348,7 +350,7 @@ void TaskDependencyManager::AcquireTaskLease(const TaskID &task_id) {
 
   auto task_lease_data = std::make_shared<TaskLeaseData>();
   task_lease_data->set_node_manager_id(client_id_.Hex());
-  task_lease_data->set_acquired_at(current_sys_time_ms());
+  task_lease_data->set_acquired_at(absl::GetCurrentTimeNanos() / 1000000);
   task_lease_data->set_timeout(it->second.lease_period);
   RAY_CHECK_OK(task_lease_table_.Add(JobID::Nil(), task_id, task_lease_data, nullptr));
 
diff --git a/src/ray/raylet/task_dependency_manager.h b/src/ray/raylet/task_dependency_manager.h
index 7effa44ed..c714ac586 100644
--- a/src/ray/raylet/task_dependency_manager.h
+++ b/src/ray/raylet/task_dependency_manager.h
@@ -6,7 +6,6 @@
 #include "ray/common/task/task.h"
 #include "ray/object_manager/object_manager.h"
 #include "ray/raylet/reconstruction_policy.h"
-#include "ray/util/util.h"
 // clang-format on
 
 namespace ray {
diff --git a/src/ray/util/util.h b/src/ray/util/util.h
index 793b548a2..1b10ffa8d 100644
--- a/src/ray/util/util.h
+++ b/src/ray/util/util.h
@@ -28,25 +28,6 @@ inline int64_t current_time_ms() {
   return ms_since_epoch.count();
 }
 
-inline int64_t current_sys_time_ms() {
-  std::chrono::milliseconds ms_since_epoch =
-      std::chrono::duration_cast<std::chrono::milliseconds>(
-          std::chrono::system_clock::now().time_since_epoch());
-  return ms_since_epoch.count();
-}
-
-inline int64_t current_sys_time_us() {
-  std::chrono::microseconds mu_since_epoch =
-      std::chrono::duration_cast<std::chrono::microseconds>(
-          std::chrono::system_clock::now().time_since_epoch());
-  return mu_since_epoch.count();
-}
-
-inline double current_sys_time_seconds() {
-  int64_t microseconds_in_seconds = 1000000;
-  return static_cast<double>(current_sys_time_us()) / microseconds_in_seconds;
-}
-
 inline ray::Status boost_to_ray_status(const boost::system::error_code &error) {
   switch (error.value()) {
   case boost::system::errc::success: