use max_mem to control stratge

chunk_codegen.py

@@ -1398,14 +1398,18 @@ class MemoryEstimator(object):
 
 class ChunkSelector(object):
     def __init__(
-        self, index_tracer: IndexTracer, memory_estimator: MemoryEstimator, stratge, max_memory=None
+        self,
+        index_tracer: IndexTracer,
+        memory_estimator: MemoryEstimator,
+        max_memory=None,
     ):
         self.index_tracer = index_tracer
         self.memory_estimator = memory_estimator
-        assert stratge in ["min_memory", "fit_memory"]
-        assert (stratge == "fit_memory" and max_memory is not None) or stratge != "fit_memory"
-        self.stratge = stratge
-        self.max_memory = max_memory  # MB
+        if max_memory is not None:
+            self.stratge = "fit_memory"
+            self.max_memory = max_memory  # MB
+        else:
+            self.stratge = "min_memory"
 
     def _select_best_chunk_region(
         self, possible_chunk_regions, chunk_infos, peak_node, max_chunk_region, mem_peak
@@ -1538,6 +1542,8 @@ class ChunkSelector(object):
             possible_chunk_regions.remove(i)
             max_region_range = 0
             best_region = None
+        if best_region is not None:
+            best_region["chunk_size"] = 2
         return best_region
 
     def _is_legal_region(self, cur_chunk_info, chunk_infos):
@@ -1563,7 +1569,7 @@ class ChunkRegionSearch(object):
         self.index_tracer.trace_index()
         self.memory_estimator = MemoryEstimator(self.index_tracer)
         self.chunk_selector = ChunkSelector(
-            self.index_tracer, self.memory_estimator, stratge="fit_memory", max_memory=max_memory
+            self.index_tracer, self.memory_estimator, max_memory=max_memory
         )
 
     def _find_peak_node(self, mem_peak):
@@ -2233,7 +2239,7 @@ if CODEGEN_AVAILABLE:
                 delete_unused_values,
                 self.meta_node,
                 self.meta_graph,
-                self.max_memory
+                self.max_memory,
             )
 
             if len(body) == 0: