diff --git a/src/databricks/sql/cloudfetch/downloader.py b/src/databricks/sql/cloudfetch/downloader.py
index 019c4ef9..697e09a5 100644
--- a/src/databricks/sql/cloudfetch/downloader.py
+++ b/src/databricks/sql/cloudfetch/downloader.py
@@ -1,15 +1,19 @@
 import logging
 from dataclasses import dataclass
-
+from datetime import datetime
 import requests
 import lz4.frame
 import threading
 import time
-
+import os
+from threading import get_ident
 from databricks.sql.thrift_api.TCLIService.ttypes import TSparkArrowResultLink
 
+logging.basicConfig(format="%(asctime)s %(message)s")
 logger = logging.getLogger(__name__)
 
+DEFAULT_CLOUD_FILE_TIMEOUT = int(os.getenv("DATABRICKS_CLOUD_FILE_TIMEOUT", 60))
+
 
 @dataclass
 class DownloadableResultSettings:
@@ -25,7 +29,7 @@ class DownloadableResultSettings:
 
     is_lz4_compressed: bool
     link_expiry_buffer_secs: int = 0
-    download_timeout: int = 60
+    download_timeout: int = DEFAULT_CLOUD_FILE_TIMEOUT
     max_consecutive_file_download_retries: int = 0
 
 
@@ -57,16 +61,27 @@ def is_file_download_successful(self) -> bool:
             else None
         )
         try:
+            msg = f"{datetime.now()} {(os.getpid(), get_ident())} wait for {timeout} for download file: startRow {self.result_link.startRowOffset}, rowCount{self.result_link.rowCount} "
+            logger.debug(
+                f"{datetime.now()} {(os.getpid(), get_ident())} wait for {timeout} for download file: startRow {self.result_link.startRowOffset}, rowCount{self.result_link.rowCount} "
+            )
+
             if not self.is_download_finished.wait(timeout=timeout):
                 self.is_download_timedout = True
                 logger.debug(
-                    "Cloud fetch download timed out after {} seconds for link representing rows {} to {}".format(
+                    "{} {} Cloud fetch download timed out after {} seconds for link representing rows {} to {}".format(
+                        datetime.now(),
+                        (os.getpid(), get_ident()),
                         self.settings.download_timeout,
                         self.result_link.startRowOffset,
                         self.result_link.startRowOffset + self.result_link.rowCount,
                     )
                 )
                 return False
+
+            logger.debug(
+                f"{datetime.now()} {(os.getpid(), get_ident())} success wait for {timeout} for download file: startRow {self.result_link.startRowOffset}, rowCount{self.result_link.rowCount} "
+            )
         except Exception as e:
             logger.error(e)
             return False
@@ -92,10 +107,22 @@ def run(self):
         session.timeout = self.settings.download_timeout
 
         try:
+            logger.debug(
+                f"{datetime.now()} {(os.getpid(), get_ident())} start download file: startRow {self.result_link.startRowOffset}, rowCount{self.result_link.rowCount}"
+            )
+
             # Get the file via HTTP request
             response = session.get(self.result_link.fileLink)
 
+            logger.debug(
+                f"{datetime.now()} {(os.getpid(), get_ident())} finish download file: startRow {self.result_link.startRowOffset}, rowCount{self.result_link.rowCount}"
+            )
+
             if not response.ok:
+                logger.error(
+                    f"{datetime.now()} {(os.getpid(), get_ident())} failed downloading file: startRow {self.result_link.startRowOffset}, rowCount{self.result_link.rowCount}"
+                )
+                logger.error(response)
                 self.is_file_downloaded_successfully = False
                 return
 
@@ -109,18 +136,27 @@ def run(self):
             self.result_file = decompressed_data
 
             # The size of the downloaded file should match the size specified from TSparkArrowResultLink
-            self.is_file_downloaded_successfully = (
-                len(self.result_file) == self.result_link.bytesNum
+            success = len(self.result_file) == self.result_link.bytesNum
+            logger.debug(
+                f"{datetime.now()} {(os.getpid(), get_ident())} download successful file: startRow {self.result_link.startRowOffset}, rowCount{self.result_link.rowCount}"
             )
+            self.is_file_downloaded_successfully = success
         except Exception as e:
+            logger.debug(
+                f"{datetime.now()} {(os.getpid(), get_ident())} exception download file: startRow {self.result_link.startRowOffset}, rowCount{self.result_link.rowCount}"
+            )
             logger.error(e)
             self.is_file_downloaded_successfully = False
 
         finally:
             session and session.close()
+            logger.debug(
+                f"{datetime.now()} {(os.getpid(), get_ident())} signal finished file: startRow {self.result_link.startRowOffset}, rowCount{self.result_link.rowCount}"
+            )
             # Awaken threads waiting for this to be true which signals the run is complete
             self.is_download_finished.set()
 
+
     def _reset(self):
         """
         Reset download-related flags for every retry of run()
diff --git a/src/databricks/sql/thrift_backend.py b/src/databricks/sql/thrift_backend.py
index 69ac760a..4a9e80c4 100644
--- a/src/databricks/sql/thrift_backend.py
+++ b/src/databricks/sql/thrift_backend.py
@@ -975,6 +975,7 @@ def fetch_results(
         arrow_schema_bytes,
         description,
     ):
+        logger.debug("ThriftBackend fetch_results")
         assert op_handle is not None
 
         req = ttypes.TFetchResultsReq(
diff --git a/src/databricks/sql/utils.py b/src/databricks/sql/utils.py
index 7c3a014b..14fa06af 100644
--- a/src/databricks/sql/utils.py
+++ b/src/databricks/sql/utils.py
@@ -156,8 +156,11 @@ def __init__(
         self.lz4_compressed = lz4_compressed
         self.description = description
 
+        # self.download_manager = ResultFileDownloadManager(
+        #     self.max_download_threads, self.lz4_compressed
+        # )
         self.download_manager = ResultFileDownloadManager(
-            self.max_download_threads, self.lz4_compressed
+            1, self.lz4_compressed
         )
         self.download_manager.add_file_links(result_links)