diff --git a/tests/test_otaclient_common/test_retry_task_map.py b/tests/test_otaclient_common/test_retry_task_map.py
index dd4d436e2..bd5a8d4bb 100644
--- a/tests/test_otaclient_common/test_retry_task_map.py
+++ b/tests/test_otaclient_common/test_retry_task_map.py
@@ -17,6 +17,7 @@
 
 import logging
 import random
+import threading
 import time
 
 import pytest
@@ -25,39 +26,48 @@
 
 logger = logging.getLogger(__name__)
 
+# ------ test setup ------ #
+WAIT_CONST = 100_000_000
+TASKS_COUNT = 2000
+MAX_CONCURRENT = 128
+MAX_WAIT_BEFORE_SUCCESS = 10
+THREAD_INIT_MSG = "thread init message"
+
 
 class _RetryTaskMapTestErr(Exception):
     """"""
 
 
+def _thread_initializer(msg: str) -> None:
+    """For testing thread worker initializer."""
+    thread_native_id = threading.get_native_id()
+    logger.info(f"thread worker #{thread_native_id} initialized: {msg}")
+
+
 class TestRetryTaskMap:
-    WAIT_CONST = 100_000_000
-    TASKS_COUNT = 2000
-    MAX_CONCURRENT = 128
-    MAX_WAIT_BEFORE_SUCCESS = 10
 
     @pytest.fixture(autouse=True)
     def setup(self):
         self._start_time = time.time()
         self._success_wait_dict = {
-            idx: random.randint(0, self.MAX_WAIT_BEFORE_SUCCESS)
-            for idx in range(self.TASKS_COUNT)
+            idx: random.randint(0, MAX_WAIT_BEFORE_SUCCESS)
+            for idx in range(TASKS_COUNT)
         }
-        self._succeeded_tasks = [False for _ in range(self.TASKS_COUNT)]
+        self._succeeded_tasks = [False for _ in range(TASKS_COUNT)]
 
     def workload_aways_failed(self, idx: int) -> int:
-        time.sleep((self.TASKS_COUNT - random.randint(0, idx)) / self.WAIT_CONST)
+        time.sleep((TASKS_COUNT - random.randint(0, idx)) / WAIT_CONST)
         raise _RetryTaskMapTestErr
 
     def workload_failed_and_then_succeed(self, idx: int) -> int:
-        time.sleep((self.TASKS_COUNT - random.randint(0, idx)) / self.WAIT_CONST)
+        time.sleep((TASKS_COUNT - random.randint(0, idx)) / WAIT_CONST)
         if time.time() > self._start_time + self._success_wait_dict[idx]:
             self._succeeded_tasks[idx] = True
             return idx
         raise _RetryTaskMapTestErr
 
     def workload_succeed(self, idx: int) -> int:
-        time.sleep((self.TASKS_COUNT - random.randint(0, idx)) / self.WAIT_CONST)
+        time.sleep((TASKS_COUNT - random.randint(0, idx)) / WAIT_CONST)
         self._succeeded_tasks[idx] = True
         return idx
 
@@ -69,48 +79,62 @@ def _exit_on_exceed_max_count():
                 raise ValueError(f"{failure_count=} > {MAX_RETRY=}")
 
         with retry_task_map.ThreadPoolExecutorWithRetry(
-            max_concurrent=self.MAX_CONCURRENT,
+            max_concurrent=MAX_CONCURRENT,
             watchdog_func=_exit_on_exceed_max_count,
+            initializer=_thread_initializer,
+            initargs=(THREAD_INIT_MSG,),
         ) as executor:
             with pytest.raises(retry_task_map.TasksEnsureFailed):
                 for _fut in executor.ensure_tasks(
-                    self.workload_aways_failed, range(self.TASKS_COUNT)
+                    self.workload_aways_failed, range(TASKS_COUNT)
                 ):
                     if _fut.exception():
                         failure_count += 1
 
     def test_retry_exceed_retry_limit(self):
+        MAX_TOTAL_RETRY = 200
+        failure_count = 0
         with retry_task_map.ThreadPoolExecutorWithRetry(
-            max_concurrent=self.MAX_CONCURRENT, max_total_retry=200
+            max_concurrent=MAX_CONCURRENT,
+            max_total_retry=MAX_TOTAL_RETRY,
+            initializer=_thread_initializer,
+            initargs=(THREAD_INIT_MSG,),
         ) as executor:
             with pytest.raises(retry_task_map.TasksEnsureFailed):
-                for _ in executor.ensure_tasks(
-                    self.workload_aways_failed, range(self.TASKS_COUNT)
+                for _fut in executor.ensure_tasks(
+                    self.workload_aways_failed, range(TASKS_COUNT)
                 ):
-                    pass
+                    if _fut.exception():
+                        failure_count += 1
+
+        assert failure_count >= MAX_TOTAL_RETRY
 
     def test_retry_finally_succeeded(self):
         count = 0
         with retry_task_map.ThreadPoolExecutorWithRetry(
-            max_concurrent=self.MAX_CONCURRENT
+            max_concurrent=MAX_CONCURRENT,
+            initializer=_thread_initializer,
+            initargs=(THREAD_INIT_MSG,),
         ) as executor:
             for _fut in executor.ensure_tasks(
-                self.workload_failed_and_then_succeed, range(self.TASKS_COUNT)
+                self.workload_failed_and_then_succeed, range(TASKS_COUNT)
             ):
                 if not _fut.exception():
                     count += 1
         assert all(self._succeeded_tasks)
-        assert self.TASKS_COUNT == count
+        assert TASKS_COUNT == count
 
     def test_succeeded_in_one_try(self):
         count = 0
         with retry_task_map.ThreadPoolExecutorWithRetry(
-            max_concurrent=self.MAX_CONCURRENT
+            max_concurrent=MAX_CONCURRENT,
+            initializer=_thread_initializer,
+            initargs=(THREAD_INIT_MSG,),
         ) as executor:
             for _fut in executor.ensure_tasks(
-                self.workload_succeed, range(self.TASKS_COUNT)
+                self.workload_succeed, range(TASKS_COUNT)
             ):
                 if not _fut.exception():
                     count += 1
         assert all(self._succeeded_tasks)
-        assert self.TASKS_COUNT == count
+        assert TASKS_COUNT == count