diff --git a/pyproject.toml b/pyproject.toml
index 262cb7c8..8504aabe 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -13,7 +13,7 @@ license = "Apache-2.0"
 dependencies = [
     "requests ~= 2.31",
     "boto3 >= 1.34.75",
-    "deadline >= 0.54.0,< 0.55",
+    "deadline >= 0.55,< 0.56",
     # Pinned to patch version due to Host Config Script runner usage of private OpenJD Sessions API.
     "openjd-sessions == 0.10.7",
     "openjd-model >= 0.8.1, < 0.10",
diff --git a/src/deadline_worker_agent/aws/deadline/__init__.py b/src/deadline_worker_agent/aws/deadline/__init__.py
index 6380ba37..072bb61e 100644
--- a/src/deadline_worker_agent/aws/deadline/__init__.py
+++ b/src/deadline_worker_agent/aws/deadline/__init__.py
@@ -841,6 +841,15 @@ def _record_attachment_download_filesystem_event(queue_id: str, file_system: str
     )
 
 
+def record_vfs_mount_telemetry_event(successfully_mounted: bool) -> None:
+    """Calls the telemetry client to record whether a VFS mount succeeded."""
+    details: Dict[str, Any] = {"successfully_mounted": successfully_mounted}
+    _get_deadline_telemetry_client().record_event(
+        event_type="com.amazon.rum.deadline.job_attachments.vfs_mount",
+        event_details=details,
+    )
+
+
 def record_sync_inputs_telemetry_event(queue_id: str, summary: SummaryStatistics) -> None:
     """Calls the telemetry client to record an event capturing the sync-inputs summary."""
     details: Dict[str, Any] = asdict(summary)
diff --git a/src/deadline_worker_agent/sessions/actions/run_attachment_download.py b/src/deadline_worker_agent/sessions/actions/run_attachment_download.py
index bfc34ccd..074a2f4d 100644
--- a/src/deadline_worker_agent/sessions/actions/run_attachment_download.py
+++ b/src/deadline_worker_agent/sessions/actions/run_attachment_download.py
@@ -29,7 +29,10 @@
     WindowsPermissionEnum,
 )
 from deadline.job_attachments._utils import _get_unique_dest_dir_name
-from deadline_worker_agent.aws.deadline import _record_attachment_download_filesystem_event
+from deadline_worker_agent.aws.deadline import (
+    _record_attachment_download_filesystem_event,
+    record_vfs_mount_telemetry_event,
+)
 
 from openjd.sessions import (
     LOG as OPENJD_LOG,
@@ -425,6 +428,7 @@ def _start_vfs(
                 fs_permission_settings=fs_permission_settings,
                 merged_manifests_by_root=merged_manifests_by_root,
                 os_env_vars=dict(session._env),  # type: ignore
+                on_mount_complete=record_vfs_mount_telemetry_event,
             )
         else:
             return False
diff --git a/src/deadline_worker_agent/sessions/actions/scripts/attachment_upload.py b/src/deadline_worker_agent/sessions/actions/scripts/attachment_upload.py
index 6983d665..60e8e355 100644
--- a/src/deadline_worker_agent/sessions/actions/scripts/attachment_upload.py
+++ b/src/deadline_worker_agent/sessions/actions/scripts/attachment_upload.py
@@ -49,6 +49,10 @@
 
 _queue_id = os.environ.get("DEADLINE_QUEUE_ID", "queue-unknown")  # Just for telemetry
 
+# Configuration constants for the S3AssetUploader used during output uploads.
+S3_MAX_POOL_CONNECTIONS = 50
+SMALL_FILE_THRESHOLD_MULTIPLIER = 20
+
 F = TypeVar("F", bound=Callable[..., Any])
 
 
@@ -288,7 +292,10 @@ def upload_output_assets(
     s3_settings = JobAttachmentS3Settings.from_s3_root_uri(s3_uri)
 
     # Initialize the S3 asset uploader
-    asset_uploader: S3AssetUploader = S3AssetUploader()
+    asset_uploader: S3AssetUploader = S3AssetUploader(
+        s3_max_pool_connections=S3_MAX_POOL_CONNECTIONS,
+        small_file_threshold_multiplier=SMALL_FILE_THRESHOLD_MULTIPLIER,
+    )
     output_manifest_info_list = []
 
     all_upload_summaries = []
diff --git a/test/unit/sessions/actions/scripts/test_attachment_upload.py b/test/unit/sessions/actions/scripts/test_attachment_upload.py
index c0a59caa..7dad2b5c 100644
--- a/test/unit/sessions/actions/scripts/test_attachment_upload.py
+++ b/test/unit/sessions/actions/scripts/test_attachment_upload.py
@@ -646,6 +646,7 @@ def test_failure_telemetry_decorator_on_upload_output_assets(
         },
     )  # Mock the environment variables
     @patch.object(attachment_upload_mod, "record_attachment_upload_latencies_telemetry_event")
+    @patch.object(attachment_upload_mod, "upload_output_assets")
     @patch.object(attachment_upload_mod, "snapshot")
     @patch.object(attachment_upload_mod, "merge")
     @patch.object(attachment_upload_mod, "parse_worker_manifest_properties")
@@ -654,6 +655,7 @@ def test_latencies_telemetry(
         mock_parse: Mock,
         mock_merge: Mock,
         mock_snapshot: Mock,
+        mock_upload: Mock,
         mock_latencies_telemetry: Mock,
         root_path_to_output_manifest: Optional[Mock],
     ):
diff --git a/test/unit/sessions/actions/test_run_attachment_download.py b/test/unit/sessions/actions/test_run_attachment_download.py
index 012eeee3..9504b459 100644
--- a/test/unit/sessions/actions/test_run_attachment_download.py
+++ b/test/unit/sessions/actions/test_run_attachment_download.py
@@ -496,6 +496,7 @@ def test_start_vfs_calling_asset_sync(
                 fs_permission_settings=ANY,
                 merged_manifests_by_root=merged_manifests_by_root,
                 os_env_vars=session._env,
+                on_mount_complete=ANY,
             )
 
     def test_start_vfs_windows_platform(