diff --git a/chunk_codegen.py b/chunk_codegen.py
index f87a3a132..cdd0b1077 100644
--- a/chunk_codegen.py
+++ b/chunk_codegen.py
@@ -1368,12 +1368,60 @@ class MemoryEstimator(object):
         return act_memory_peak_log, act_memory_after_node_log, active_node_list_log
 
 
+class ChunkSelector(object):
+    def __init__(self, index_tracer: IndexTracer, stratge) -> None:
+        self.index_tracer = index_tracer
+        assert stratge in ['min_memory', 'fit_memory']
+        self.stratge = stratge
+        self.max_memory = 800  # MB
+    
+    def _select_best_chunk_region(self, possible_chunk_regions, chunk_infos):
+        if self.stratge == 'min_memory':
+            best_region = self._select_min_memory_chunk_region(possible_chunk_regions, chunk_infos)
+        elif self.stratge == 'fit_memory':
+            pass
+        else:
+            raise RuntimeError()
+        return best_region
+    
+    def _select_min_memory_chunk_region(self, possible_chunk_regions, chunk_infos):
+        max_region_range = 0
+        best_region = None
+        while len(possible_chunk_regions) > 0:
+            for i in possible_chunk_regions:
+                if i["region"][1] - i["region"][0] > max_region_range:
+                    best_region = i
+                    max_region_range = i["region"][1] - i["region"][0]
+            if self._is_legal_region(best_region, chunk_infos):
+                break
+            possible_chunk_regions.remove(i)
+            max_region_range = 0
+            best_region = None
+        return best_region
+
+    def _is_legal_region(self, cur_chunk_info, chunk_infos):
+        (chunk_region_start, chunk_region_end) = cur_chunk_info["region"]
+        if cur_chunk_info in chunk_infos:
+            return False
+        if chunk_region_end < chunk_region_start:
+            return False
+        for i in chunk_infos:
+            region = i["region"]
+            if not (
+                (chunk_region_start > region[1] and chunk_region_end > region[1])
+                or (chunk_region_start < region[0] and chunk_region_end < region[0])
+            ):
+                return False
+        return True
+
+
 class ChunkRegionSearch(object):
     def __init__(self, gm) -> None:
         self.gm = gm
         self.index_tracer = IndexTracer(list(gm.graph.nodes))
         self.index_tracer.trace_index()
         self.memory_estimator = MemoryEstimator(self.index_tracer)
+        self.chunk_selector = ChunkSelector(self.index_tracer, stratge="min_memory")
 
     def _find_peak_node(self, mem_peak):
         max_value = max(mem_peak)
@@ -1516,36 +1564,6 @@ class ChunkRegionSearch(object):
                     possible_chunk_region.extend(chunk_info)
         return possible_chunk_region
 
-    def _search_best_chunk_region(self, possible_chunk_regions, chunk_infos):
-        max_region_range = 0
-        best_region = None
-        while len(possible_chunk_regions) > 0:
-            for i in possible_chunk_regions:
-                if i["region"][1] - i["region"][0] > max_region_range:
-                    best_region = i
-                    max_region_range = i["region"][1] - i["region"][0]
-            if self._is_legal_region(best_region, chunk_infos):
-                break
-            possible_chunk_regions.remove(i)
-            max_region_range = 0
-            best_region = None
-        return best_region
-
-    def _is_legal_region(self, cur_chunk_info, chunk_infos):
-        (chunk_region_start, chunk_region_end) = cur_chunk_info["region"]
-        if cur_chunk_info in chunk_infos:
-            return False
-        if chunk_region_end < chunk_region_start:
-            return False
-        for i in chunk_infos:
-            region = i["region"]
-            if not (
-                (chunk_region_start > region[1] and chunk_region_end > region[1])
-                or (chunk_region_start < region[0] and chunk_region_end < region[0])
-            ):
-                return False
-        return True
-
     def _step_search(self, mem_peak, active_node, chunk_regions):
         peak_node = self._find_peak_node(mem_peak)
         max_chunk_region = self._search_max_chunk_region(
@@ -1556,7 +1574,7 @@ class ChunkRegionSearch(object):
         possible_chunk_regions = self._search_possible_chunk_regions(
             max_chunk_region, peak_node
         )
-        best_chunk_region = self._search_best_chunk_region(
+        best_chunk_region = self.chunk_selector._select_best_chunk_region(
             possible_chunk_regions, chunk_regions
         )
         best_chunk_region = self.index_tracer.reorder_all(best_chunk_region)