diff --git a/src/ray/raylet/worker_pool.cc b/src/ray/raylet/worker_pool.cc
index 117d0a506615f..f350b610ca683 100644
--- a/src/ray/raylet/worker_pool.cc
+++ b/src/ray/raylet/worker_pool.cc
@@ -253,6 +253,8 @@ void WorkerPool::RemoveWorkerProcess(State &state,
   state.worker_processes.erase(proc_startup_token);
 }
 
+// Intuition is, job id only decides which parameters to use for the executable, reduce a
+// few of them.
 std::pair<std::vector<std::string>, ProcessEnvironment>
 WorkerPool::BuildProcessCommandArgs(const Language &language,
                                     rpc::JobConfig *job_config,
@@ -357,6 +359,10 @@ WorkerPool::BuildProcessCommandArgs(const Language &language,
     worker_command_args.push_back("--worker-launch-time-ms=" +
                                   std::to_string(current_sys_time_ms()));
     worker_command_args.push_back("--node-id=" + node_id_.Hex());
+    if (!is_prefetch) {
+      worker_command_args.push_back("--runtime-env-hash=" +
+                                    std::to_string(runtime_env_hash));
+    }
     worker_command_args.push_back("--runtime-env-hash=" +
                                   std::to_string(runtime_env_hash));
   } else if (language == Language::CPP) {
@@ -368,8 +374,10 @@ WorkerPool::BuildProcessCommandArgs(const Language &language,
 
   if (serialized_runtime_env_context != "{}" && !serialized_runtime_env_context.empty()) {
     worker_command_args.push_back("--language=" + Language_Name(language));
-    worker_command_args.push_back("--serialized-runtime-env-context=" +
-                                  serialized_runtime_env_context);
+    if (!is_prefetch) {
+      worker_command_args.push_back("--serialized-runtime-env-context=" +
+                                    serialized_runtime_env_context);
+    }
   } else if (language == Language::PYTHON && worker_command_args.size() >= 2 &&
              worker_command_args[1].find(kSetupWorkerFilename) != std::string::npos) {
     // Check that the arg really is the path to the setup worker before erasing it, to
@@ -384,6 +392,8 @@ WorkerPool::BuildProcessCommandArgs(const Language &language,
     worker_command_args.push_back("--ray-debugger-external");
   }
 
+  is_prefetch = false;
+
   ProcessEnvironment env;
   if (!IsIOWorkerType(worker_type)) {
     // We pass the job ID to worker processes via an environment variable, so we don't
@@ -1482,6 +1492,8 @@ void WorkerPool::PrestartWorkers(const TaskSpecification &task_spec,
   }
 }
 
+thread_local bool is_prefetch = false;
+
 void WorkerPool::PrestartWorkersInternal(const TaskSpecification &task_spec,
                                          int64_t num_needed) {
   RAY_LOG(DEBUG) << "PrestartWorkers " << num_needed;
@@ -1507,6 +1519,7 @@ void WorkerPool::PrestartWorkersInternal(const TaskSpecification &task_spec,
                            << setup_error_message;
             return;
           }
+          is_prefetch = true;
           PopWorkerStatus status;
           StartWorkerProcess(task_spec.GetLanguage(),
                              rpc::WorkerType::WORKER,