[core] Make PinObjectIDs RPC Fault Tolerant

src/fakes/ray/object_manager/plasma/fake_plasma_client.h

@@ -71,13 +71,19 @@ class FakePlasmaClient : public PlasmaClientInterface {
   Status Get(const std::vector<ObjectID> &object_ids,
              int64_t timeout_ms,
              std::vector<plasma::ObjectBuffer> *object_buffers) override {
+    object_buffers->reserve(object_ids.size());
     for (const auto &id : object_ids) {
-      auto &buffers = objects_in_plasma_[id];
-      plasma::ObjectBuffer shm_buffer{std::make_shared<SharedMemoryBuffer>(
-                                          buffers.first.data(), buffers.first.size()),
-                                      std::make_shared<SharedMemoryBuffer>(
-                                          buffers.second.data(), buffers.second.size())};
-      object_buffers->emplace_back(shm_buffer);
+      if (objects_in_plasma_.contains(id)) {
+        auto &buffers = objects_in_plasma_[id];
+        plasma::ObjectBuffer shm_buffer{
+            std::make_shared<SharedMemoryBuffer>(buffers.first.data(),
+                                                 buffers.first.size()),
+            std::make_shared<SharedMemoryBuffer>(buffers.second.data(),
+                                                 buffers.second.size())};
+        object_buffers->emplace_back(shm_buffer);
+      } else {
+        object_buffers->emplace_back(plasma::ObjectBuffer{});
+      }
     }
     return Status::OK();
   }

src/ray/raylet/tests/node_manager_test.cc

@@ -1067,6 +1067,58 @@ TEST_F(NodeManagerTest, TestHandleCancelWorkerLeaseNoLeaseIdempotent) {
   ASSERT_EQ(reply2.success(), false);
 }
 
+class PinObjectIDsIdempotencyTest : public NodeManagerTest,
+                                    public ::testing::WithParamInterface<bool> {};
+
+TEST_P(PinObjectIDsIdempotencyTest, TestHandlePinObjectIDsIdempotency) {
+  // object_exists: determines whether we add an object to the plasma store which is used
+  // for pinning.
+  // object_exists == true: an object is added to the plasma store and PinObjectIDs is
+  // expected to succeed. A true boolean value is inserted at the index of the object
+  // in reply.successes.
+  // object_exists == false: an object is not added to the plasma store. PinObjectIDs will
+  // still succeed and not return an error when trying to pin a non-existent object, but
+  // will instead at the index of the object in reply.successes insert a false
+  // boolean value.
+  const bool object_exists = GetParam();
+  ObjectID id = ObjectID::FromRandom();
+
+  if (object_exists) {
+    rpc::Address owner_addr;
+    plasma::flatbuf::ObjectSource source = plasma::flatbuf::ObjectSource::CreatedByWorker;
+    RAY_UNUSED(mock_store_client_->TryCreateImmediately(
+        id, owner_addr, 1024, nullptr, 1024, nullptr, source, 0));
+  }
+
+  rpc::PinObjectIDsRequest pin_request;
+  pin_request.add_object_ids(id.Binary());
+
+  rpc::PinObjectIDsReply reply1;
+  node_manager_->HandlePinObjectIDs(
+      pin_request,
+      &reply1,
+      [](Status s, std::function<void()> success, std::function<void()> failure) {});
+
+  int64_t primary_bytes = local_object_manager_->GetPrimaryBytes();
+  rpc::PinObjectIDsReply reply2;
+  node_manager_->HandlePinObjectIDs(
+      pin_request,
+      &reply2,
+      [](Status s, std::function<void()> success, std::function<void()> failure) {});
+
+  // For each invocation of HandlePinObjectIDs, we expect the size of reply.successes and
+  // the boolean values it contains to not change.
+  EXPECT_EQ(reply1.successes_size(), 1);
+  EXPECT_EQ(reply1.successes(0), object_exists);
+  EXPECT_EQ(reply2.successes_size(), 1);
+  EXPECT_EQ(reply2.successes(0), object_exists);
+  EXPECT_EQ(local_object_manager_->GetPrimaryBytes(), primary_bytes);
+}
+
+INSTANTIATE_TEST_SUITE_P(PinObjectIDsIdempotencyVariations,
+                         PinObjectIDsIdempotencyTest,
+                         testing::Bool());
+
 }  // namespace ray::raylet
 
 int main(int argc, char **argv) {

src/ray/rpc/raylet/raylet_client.cc

@@ -338,12 +338,13 @@ void RayletClient::PinObjectIDs(
     pins_in_flight_--;
     callback(status, std::move(reply));
   };
-  INVOKE_RPC_CALL(NodeManagerService,
-                  PinObjectIDs,
-                  request,
-                  rpc_callback,
-                  grpc_client_,
-                  /*method_timeout_ms*/ -1);
+  INVOKE_RETRYABLE_RPC_CALL(retryable_grpc_client_,
+                            NodeManagerService,
+                            PinObjectIDs,
+                            request,
+                            rpc_callback,
+                            grpc_client_,
+                            /*method_timeout_ms*/ -1);
 }
 
 void RayletClient::ShutdownRaylet(