From 7611e484ec5b95c18fbdcd6a493944fdccb45367 Mon Sep 17 00:00:00 2001
From: Zhijun Fu <37800433+zhijunfu@users.noreply.github.com>
Date: Thu, 5 Dec 2019 13:37:52 +0800
Subject: [PATCH] properly handle a forwarded task that gets forwarded back
 (#6271)

---
 src/ray/raylet/node_manager.cc | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/ray/raylet/node_manager.cc b/src/ray/raylet/node_manager.cc
index fae949196..2714451a9 100644
--- a/src/ray/raylet/node_manager.cc
+++ b/src/ray/raylet/node_manager.cc
@@ -2814,6 +2814,12 @@ void NodeManager::ForwardTask(
 
   client->ForwardTask(request, [this, on_error, task, task_id, node_id](
                                    Status status, const rpc::ForwardTaskReply &reply) {
+    if (local_queues_.HasTask(task_id)) {
+      // It must have been forwarded back to us if it's in the queue again
+      // so just return here.
+      return;
+    }
+
     if (status.ok()) {
       const auto &spec = task.GetTaskSpecification();
       // Mark as forwarded so that the task and its lineage are not