diff --git a/analytics/analytics/analytic_unit_worker.py b/analytics/analytics/analytic_unit_worker.py
index 2414e2f..7cddfe1 100644
--- a/analytics/analytics/analytic_unit_worker.py
+++ b/analytics/analytics/analytic_unit_worker.py
@@ -57,7 +57,14 @@ class AnalyticUnitWorker:
           'lastDetectionTime': None
         }
 
-        for chunk in get_intersected_chunks(data, chunk_intersection, chunk_size):
+        chunks = []
+        # XXX: get_chunks(data, chunk_size) == get_intersected_chunks(data, 0, chunk_size)
+        if self._detector.is_detection_intersected():
+            chunks = get_intersected_chunks(data, chunk_intersection, chunk_size)
+        else:
+            chunks = get_chunks(data, chunk_size)
+
+        for chunk in chunks:
             await asyncio.sleep(0)
             chunk_dataframe = prepare_data(chunk)
             detected = self._detector.detect(chunk_dataframe, cache)
@@ -86,7 +93,7 @@ class AnalyticUnitWorker:
             self.__append_detection_result(detection_result, detected)
         
         detection_result['segments'] = self._detector.get_intersections(detection_result['segments'])
-
+        
         if detection_result['lastDetectionTime'] is None:
             return None
         else:
diff --git a/analytics/analytics/detectors/anomaly_detector.py b/analytics/analytics/detectors/anomaly_detector.py
index 400ea3a..704907a 100644
--- a/analytics/analytics/detectors/anomaly_detector.py
+++ b/analytics/analytics/detectors/anomaly_detector.py
@@ -7,6 +7,7 @@ from analytic_types.data_bucket import DataBucket
 from detectors import Detector
 from models import ModelCache
 import utils
+from analytic_types import AnalyticUnitId
 
 MAX_DEPENDENCY_LEVEL = 100
 MIN_DEPENDENCY_FACTOR = 0.1
@@ -15,7 +16,8 @@ logger = logging.getLogger('ANOMALY_DETECTOR')
 
 class AnomalyDetector(Detector):
 
-    def __init__(self, *args, **kwargs):
+    def __init__(self, analytic_unit_id: AnalyticUnitId):
+        self.analytic_unit_id = analytic_unit_id
         self.bucket = DataBucket()
 
     def train(self, dataframe: pd.DataFrame, payload: Union[list, dict], cache: Optional[ModelCache]) -> ModelCache:
@@ -28,7 +30,10 @@ class AnomalyDetector(Detector):
 
     def detect(self, dataframe: pd.DataFrame, cache: Optional[ModelCache]) -> dict:
         data = dataframe['value']
-        last_values = None
+        alpha = cache['alpha']
+        confidence = cache['confidence']
+
+        last_value = None
         if cache is not None:
             last_values = cache.get('last_values')
 
@@ -55,14 +60,23 @@ class AnomalyDetector(Detector):
         }
 
     def consume_data(self, data: pd.DataFrame, cache: Optional[ModelCache]) -> Optional[dict]:
-        self.detect(data, cache)
+        if cache is None:
+            msg = f'consume_data get invalid cache {cache} for task {self.analytic_unit_id}'
+            logging.debug(msg)
+            raise ValueError(msg)
 
+        data_without_nan = data.dropna()
 
-    def get_window_size(self, cache: Optional[ModelCache]) -> int:
-        '''
-        get the number of values that will affect the next value
-        '''
+        if len(data_without_nan) == 0:
+            return None
+
+        self.bucket.receive_data(data_without_nan)
 
+        if len(self.bucket.data) >= self.get_window_size(cache):
+            self.detect(self.bucket, cache)
+
+
+    def get_window_size(self, cache: Optional[ModelCache]) -> int:
         if cache is None:
             raise ValueError('anomaly detector got None cache')
         
@@ -76,3 +90,6 @@ class AnomalyDetector(Detector):
         segments = utils.merge_intersecting_intervals(segments)
         segments = [{'from': segment[0], 'to': segment[1]} for segment in segments]
         return segments
+
+    def is_detection_intersected(self) -> bool:
+        return False
diff --git a/analytics/analytics/detectors/detector.py b/analytics/analytics/detectors/detector.py
index def7c3c..b0f891b 100644
--- a/analytics/analytics/detectors/detector.py
+++ b/analytics/analytics/detectors/detector.py
@@ -28,3 +28,6 @@ class Detector(ABC):
     @abstractmethod
     def get_intersections(self, segments: List[dict]) -> List[dict]:
         pass
+
+    def is_detection_intersected(self) -> bool:
+        return True