support USE_SHARED_MEMORY=True in DBSampler with Global GT database

pcdet/datasets/augmentor/database_sampler.py

@@ -25,12 +25,12 @@ class DataBaseSampler(object):
                 infos = pickle.load(f)
                 [self.db_infos[cur_class].extend(infos[cur_class]) for cur_class in class_names]
         
+
         for func_name, val in sampler_cfg.PREPARE.items():
             self.db_infos = getattr(self, func_name)(self.db_infos, val)
 
         self.use_shared_memory = sampler_cfg.get('USE_SHARED_MEMORY', False)
-        if self.use_shared_memory:
-            self.load_db_to_shared_memory()
+        self.gt_database_data_key = self.load_db_to_shared_memory() if self.use_shared_memory else None
 
         self.sample_groups = {}
         self.sample_class_num = {}
@@ -58,21 +58,19 @@ class DataBaseSampler(object):
     def load_db_to_shared_memory(self):
         self.logger.info('Loading GT database to shared memory')
         cur_rank, num_gpus = common_utils.get_dist_info()
-        for cur_class in self.class_names:
-            cur_info_list = self.db_infos[cur_class]
-            cur_info_list = cur_info_list[cur_rank::num_gpus]
 
-            for info in cur_info_list:
-                file_path = self.root_path / info['path']
-                sa_key = info['path'].replace('/', '___')
-                if os.path.exists(f"/dev/shm/{sa_key}"):
-                    continue
+        assert self.sampler_cfg.DB_DATA_PATH.__len__() == 1, 'Current only support single DB_DATA'
+        db_data_path = self.root_path.resolve() / self.sampler_cfg.DB_DATA_PATH[0]
+        sa_key = self.sampler_cfg.DB_DATA_PATH[0]
             
-                obj_points = np.fromfile(str(file_path), dtype=np.float32).reshape([-1, self.sampler_cfg.NUM_POINT_FEATURES])
-                common_utils.sa_create(f"shm://{sa_key}", obj_points)
+        if cur_rank % num_gpus == 0 and not os.path.exists(f"/dev/shm/{sa_key}"):
+            gt_database_data = np.load(db_data_path)
+            common_utils.sa_create(f"shm://{sa_key}", gt_database_data)
             
+        if num_gpus > 1:
             dist.barrier()
         self.logger.info('GT database has been saved to shared memory')
+        return sa_key
 
     def filter_by_difficulty(self, db_infos, removed_difficulty):
         new_db_infos = {}
@@ -155,10 +153,15 @@ class DataBaseSampler(object):
             data_dict.pop('road_plane')
 
         obj_points_list = []
+        if self.use_shared_memory:
+            gt_database_data = SharedArray.attach(f"shm://{self.gt_database_data_key}")
+        else:
+            gt_database_data = None 
+
         for idx, info in enumerate(total_valid_sampled_dict):
             if self.use_shared_memory:
-                sa_key = info['path'].replace('/', '___')
-                obj_points = SharedArray.attach(f"shm://{sa_key}").copy()
+                start_offset, end_offset = info['global_data_offset']
+                obj_points = gt_database_data[start_offset:end_offset]
             else:
                 file_path = self.root_path / info['path']
                 obj_points = np.fromfile(str(file_path), dtype=np.float32).reshape(

tools/cfgs/dataset_configs/waymo_dataset.yaml

@@ -24,6 +24,12 @@ DATA_AUGMENTOR:
           USE_ROAD_PLANE: False
           DB_INFO_PATH:
               - waymo_processed_data_v0_3_1_waymo_dbinfos_train_sampled_1.pkl
+              # - waymo_processed_data_v0_3_1_waymo_dbinfos_train_sampled_1_global.pkl
+
+          USE_SHARED_MEMORY: False
+          DB_DATA_PATH: 
+              - waymo_processed_data_v0_3_1_waymo_dbinfos_train_sampled_1_global.npy
+
           PREPARE: {
              filter_by_min_points: ['Vehicle:5', 'Pedestrian:5', 'Cyclist:5'],
              filter_by_difficulty: [-1],