快速入门

接口调用介绍

1. 初始化框架。在main.py中调用init接口，传入初始化框架需要的相关参数。相关参数请参见参数说明。

   # nbatch function needs to be used together with the prefetch and host_vocabulary_size != 0
   init(use_mpi=use_mpi,
        train_steps=TRAIN_steps,
        eval_steps=EVAL_STEPS,
        use_dynamic=use_dynamic,
        use_hot=use_hot,
        use_dynamic_expansion=use_dynamic_expansion)

2. 定义数据集。在main.py中调用get_asc_insert_func接口，创建数据集并对数据集进行预处理。相关参数请参见参数说明。

       if not MODIFY_GRAPH_FLAG:
           insert_fn = get_asc_insert_func(tgt_key_specs=feature_spec_list, is_training=is_training, dump_graph=dump_graph)
           dataset = dataset.map(insert_fn)
       dataset = dataset.prefetch(100)
       iterator = dataset.make_initializable_iterator()
       batch = iterator.get_next()
       return batch, iterator

3. 定义优化器。在optimizer.py中定义优化器，支持的优化器类型和相关参数请参见优化器。

   # coding: UTF-8
   import logging
   import tensorflow as tf
   from mx_rec.optimizers.lazy_adam import create_hash_optimizer
   from mx_rec.optimizers.lazy_adam_by_addr import create_hash_optimizer_by_address
   from mx_rec.util.initialize import get_use_dynamic_expansion
   def get_dense_and_sparse_optimizer(cfg):
       dense_optimizer = tf.compat.v1.train.AdamOptimizer(learning_rate=cfg.learning_rate)
       use_dynamic_expansion = get_use_dynamic_expansion()
       if use_dynamic_expansion:
           sparse_optimizer = create_hash_optimizer_by_address(learning_rate=cfg.learning_rate)
           logging.info("optimizer lazy_adam_by_addr")
       else:
           sparse_optimizer = create_hash_optimizer(learning_rate=cfg.learning_rate)
           logging.info("optimizer lazy_adam")
       return dense_optimizer, sparse_optimizer

4. 建立稀疏表。在main.py中调用create_table接口，建立稀疏表，创建稀疏网络层。相关参数请参见参数说明。

   optimizer_list = [get_dense_and_sparse_optimizer(cfg) for _ in range(2)]
   sparse_optimizer_list = [sparse_optimizer for dense_optimizer, sparse_optimizer in optimizer_list]
   user_hashtable = create_table(key_dtype=tf.int64,
                                 dim=tf.TensorShape([cfg.user_hashtable_dim]),
                                 name='user_table',
                                 emb_initializer=tf.compat.v1.truncated_normal_initializer(),
                                 device_vocabulary_size=cfg.user_vocab_size * 10,
                                 host_vocabulary_size=0,  # cfg.user_vocab_size * 100, # for h2d test
                                 optimizer_list=sparse_optimizer_list)
   item_hashtable = create_table(key_dtype=tf.int64,
                                 dim=tf.TensorShape([cfg.item_hashtable_dim]),
                                 name='item_table',
                                 emb_initializer=tf.compat.v1.truncated_normal_initializer(),
                                 device_vocabulary_size=cfg.item_vocab_size * 10,
                                 host_vocabulary_size=0,  # cfg.user_vocab_size * 100, # for h2d test
                                 optimizer_list=sparse_optimizer_list)

5. 建立计算图。传入稀疏网络层和特征列表，创建模型计算图，在计算图中调用sparse_lookup进行特征查询和误差计算。相关参数请参见参数说明。

   def model_forward(input_list, batch, is_train, modify_graph, config_dict=None):
       embedding_list = []
       feature_list, hash_table_list, send_count_list = input_list
       for feature, hash_table, send_count in zip(feature_list, hash_table_list, send_count_list):
           access_and_evict_config = None
           if isinstance(config_dict, dict):
               access_and_evict_config = config_dict.get(hash_table.table_name)
           embedding = sparse_lookup(hash_table, feature, send_count, is_train=is_train,
                                     access_and_evict_config=access_and_evict_config,
                                     name=hash_table.table_name + "_lookup", modify_graph=modify_graph, batch=batch)
           reduced_embedding = tf.reduce_sum(embedding, axis=1, keepdims=False)
           embedding_list.append(reduced_embedding)
       my_model = MyModel()
       my_model(embedding_list, batch["label_0"], batch["label_1"])
       return my_model

6. 定义梯度计算和优化过程。在main.py中调用get_dense_and_sparse_variable接口，得到密集网络层和稀疏网络层的参数，通过优化器计算梯度并执行优化。接口说明请参见get_dense_and_sparse_variable。

   train_iterator, train_model = build_graph([user_hashtable, item_hashtable], is_train=True,
                                                 feature_spec_list=train_feature_spec_list,
                                                 config_dict=ACCESS_AND_EVICT, batch_number=cfg.batch_number)
   eval_iterator, eval_model = build_graph([user_hashtable, item_hashtable], is_train=False,
                                               feature_spec_list=eval_feature_spec_list,
                                               config_dict=ACCESS_AND_EVICT, batch_number=cfg.batch_number)
   dense_variables, sparse_variables = get_dense_and_sparse_variable()

7. 启动数据加载和预处理。在main.py中调用modify_graph_and_start_emb_cache（改图模式）/start_asc_pipeline（非改图模式）接口，启动数据流水线（示例代码中使用if判断配置文件中的MODIFY_GRAPH_FLAG来控制是否使用改图模式）。接口说明请参见modify_graph_and_start_emb_cache。

   saver = tf.compat.v1.train.Saver()
       if MODIFY_GRAPH_FLAG:
           logging.info("start to modifying graph")
           modify_graph_and_start_emb_cache(dump_graph=True)
       else:
           start_asc_pipeline()
       with tf.compat.v1.Session(config=sess_config(dump_data=False)) as sess:
           if MODIFY_GRAPH_FLAG:
               sess.run(get_initializer(True))
           else:
               sess.run(train_iterator.initializer)
           sess.run(tf.compat.v1.global_variables_initializer())
           EPOCH = 0
           if os.path.exists(f"./saved-model/sparse-model-{rank_id}-%d" % 0):
               saver.restore(sess, f"./saved-model/model-{rank_id}-%d" % 0)
           else:
               saver.save(sess, f"./saved-model/model-{rank_id}", global_step=0)
           for i in range(1, 201):
               logging.info(f"################    training at step {i}    ################")
               try:
                   sess.run([train_ops, train_model.loss_list])
               except tf.errors.OutOfRangeError:
                   logging.info(f"Encounter the end of Sequence for training.")
                   break
               else:
                   if i % TRAIN_INTERVAL == 0:
                       EPOCH += 1
                       evaluate()
                   if i % SAVING_INTERVAL == 0:
                       saver.save(sess, f"./saved-model/model-{rank_id}", global_step=i)
           saver.save(sess, f"./saved-model/model-{rank_id}", global_step=i)

8. 启动Session计算并在训练过程中保存模型。在main.py中调用saver接口，启动Session计算并在训练过程中保存模型。

   saver = tf.compat.v1.train.Saver()
       if MODIFY_GRAPH_FLAG:
           logging.info("start to modifying graph")
           modify_graph_and_start_emb_cache(dump_graph=True)
       else:
           start_asc_pipeline()
       with tf.compat.v1.Session(config=sess_config(dump_data=False)) as sess:
           if MODIFY_GRAPH_FLAG:
               sess.run(get_initializer(True))
           else:
               sess.run(train_iterator.initializer)
           sess.run(tf.compat.v1.global_variables_initializer())
           EPOCH = 0
           if os.path.exists(f"./saved-model/sparse-model-{rank_id}-%d" % 0):
               saver.restore(sess, f"./saved-model/model-{rank_id}-%d" % 0)
           else:
               saver.save(sess, f"./saved-model/model-{rank_id}", global_step=0)
           for i in range(1, 201):
               logging.info(f"################    training at step {i}    ################")
               try:
                   sess.run([train_ops, train_model.loss_list])
               except tf.errors.OutOfRangeError:
                   logging.info(f"Encounter the end of Sequence for training.")
                   break
               else:
                   if i % TRAIN_INTERVAL == 0:
                       EPOCH += 1
                       evaluate()
                   if i % SAVING_INTERVAL == 0:
                       saver.save(sess, f"./saved-model/model-{rank_id}", global_step=i)
           saver.save(sess, f"./saved-model/model-{rank_id}", global_step=i)

9. 关闭数据流释放资源。在main.py中调用terminate_config_initializer，关闭数据流释放资源。接口说明请参见terminate_config_initializer。

   terminate_config_initializer()
   logging.info("Demo done!")

启动模型训练