diff --git a/apiserver/apimodels/events.py b/apiserver/apimodels/events.py
index 0eca4e2..70cab67 100644
--- a/apiserver/apimodels/events.py
+++ b/apiserver/apimodels/events.py
@@ -20,9 +20,7 @@ class HistogramRequestBase(Base):
 
 class MetricVariants(Base):
     metric: str = StringField(required=True)
-    variants: Sequence[str] = ListField(
-        items_types=str, validators=Length(minimum_value=1)
-    )
+    variants: Sequence[str] = ListField(items_types=str)
 
 
 class ScalarMetricsIterHistogramRequest(HistogramRequestBase):
diff --git a/apiserver/bll/task/task_cleanup.py b/apiserver/bll/task/task_cleanup.py
index 3a39960..bfa5a65 100644
--- a/apiserver/bll/task/task_cleanup.py
+++ b/apiserver/bll/task/task_cleanup.py
@@ -130,14 +130,14 @@ def collect_debug_image_urls(company: str, task: str) -> Set[str]:
     if not metrics:
         return set()
 
-    task_metrics = {task: set(metrics)}
+    task_metrics = {task: {m: [] for m in metrics}}
     scroll_id = None
     urls = set()
     while True:
         res = event_bll.debug_images_iterator.get_task_events(
             company_id=company,
             task_metrics=task_metrics,
-            iter_count=100,
+            iter_count=10,
             state_id=scroll_id,
         )
         if not res.metric_events or not any(