Tensorflow Adam Multigpu梯度

Question

我正在嘗試使用ADAM優化在tensorflow上實現多個gpu網絡。

我正在處理來自Cifar10_multigpu的代碼，但它看起來當梯度調用第二個塔時，它會調用第一個和第二個塔的平均生成誤差的梯度。 兩個塔的代碼是這樣

for d in devs: 
     with tf.device(d): 
      with tf.name_scope('%s_%d' % (tf_model.TOWER_NAME, i)) as scope: 
       loss = tower_loss(scope) 
       tf.get_variable_scope().reuse_variables() 
       summaries = tf.get_collection(tf.GraphKeys.SUMMARIES, scope) 
       grads = opt.compute_gradients(loss) 
       print('\n'.join('{}: {}'.format(*k) for k in enumerate(grads))) 
       tower_grads.append(grads) 
     i +=1 

並且這產生每個塔：

stream, target= placeholder_inputs(FLAGS.batch_size*tf_model.ANGLES/FLAGS.num_gpus) 
    logits = tf_model.inference_noisy_simulate(stream) 
    _ = tf_model.loss(logits, target) 
    losses = tf.get_collection('losses', scope) 
    total_loss = tf.add_n(losses, name='total_loss') 

看梯度第一塔產生這樣的：

0: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca11d0ae10>) 
1: (<tf.Tensor 'tower_0/gradients/tower_0/conv1/Conv2D_grad/tuple/control_dependency_1:0' shape=(1, 1, 8, 16) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c351b10>) 
2: (<tf.Tensor 'tower_0/gradients/tower_0/conv1/BiasAdd_grad/tuple/control_dependency_1:0' shape=(16,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c380dd0>) 
3: (<tf.Tensor 'tower_0/gradients/tower_0/conv2/Conv2D_grad/tuple/control_dependency_1:0' shape=(45, 4, 16, 16) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c351a10>) 
4: (<tf.Tensor 'tower_0/gradients/tower_0/conv2/BiasAdd_grad/tuple/control_dependency_1:0' shape=(16,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c3a6dd0>) 
5: (<tf.Tensor 'tower_0/gradients/tower_0/conv3/Conv2D_grad/tuple/control_dependency_1:0' shape=(45, 4, 16, 32) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c3a6490>) 
6: (<tf.Tensor 'tower_0/gradients/tower_0/conv3/BiasAdd_grad/tuple/control_dependency_1:0' shape=(32,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c351990>) 
7: (<tf.Tensor 'tower_0/gradients/tower_0/conv4/Conv2D_grad/tuple/control_dependency_1:0' shape=(45, 4, 32, 64) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c351890>) 
8: (<tf.Tensor 'tower_0/gradients/tower_0/conv4/BiasAdd_grad/tuple/control_dependency_1:0' shape=(64,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c3b7790>) 
9: (<tf.Tensor 'tower_0/gradients/tower_0/conv5/Conv2D_grad/tuple/control_dependency_1:0' shape=(45, 4, 64, 128) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c2d9110>) 
10: (<tf.Tensor 'tower_0/gradients/tower_0/conv5/BiasAdd_grad/tuple/control_dependency_1:0' shape=(128,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c2849d0>) 
11: (<tf.Tensor 'tower_0/gradients/tower_0/conv6/Conv2D_grad/tuple/control_dependency_1:0' shape=(45, 4, 128, 256) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c2e6f10>) 
12: (<tf.Tensor 'tower_0/gradients/tower_0/conv6/BiasAdd_grad/tuple/control_dependency_1:0' shape=(256,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c2afed0>) 
13: (<tf.Tensor 'tower_0/gradients/tower_0/fc1/MatMul_grad/tuple/control_dependency_1:0' shape=(18944, 4096) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c1f9550>) 
14: (<tf.Tensor 'tower_0/gradients/tower_0/fc1/add_grad/tuple/control_dependency_1:0' shape=(4096,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c214a10>) 
15: (<tf.Tensor 'tower_0/gradients/tower_0/fc1_1/MatMul_grad/tuple/control_dependency_1:0' shape=(4096, 1024) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c23dfd0>) 
16: (<tf.Tensor 'tower_0/gradients/tower_0/fc1_1/add_grad/tuple/control_dependency_1:0' shape=(1024,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c269bd0>) 
17: (<tf.Tensor 'tower_0/gradients/tower_0/softmax_linear/MatMul_grad/tuple/control_dependency_1:0' shape=(1024, 360) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c1d1a50>) 
18: (<tf.Tensor 'tower_0/gradients/tower_0/softmax_linear/softmax_linear_grad/tuple/control_dependency_1:0' shape=(360,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c1def50>) 

第二個生成這個;

0: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca11d0ae10>) 
1: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c351b10>) 
2: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c380dd0>) 
3: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c351a10>) 
4: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c3a6dd0>) 
5: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c3a6490>) 
6: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c351990>) 
7: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c351890>) 
8: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c3b7790>) 
9: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c2d9110>) 
10: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c2849d0>) 
11: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c2e6f10>) 
12: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c2afed0>) 
13: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c1f9550>) 
14: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c214a10>) 
15: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c23dfd0>) 
16: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c269bd0>) 
17: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c1d1a50>) 
18: (None, <tensorflow.python.ops.variables.Variable object at 0x7fca0c1def50>) 
19: (<tf.Tensor 'tower_1/gradients/tower_1/conv1/Conv2D_grad/tuple/control_dependency_1:0' shape=(1, 1, 8, 16) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0c178c50>) 
20: (<tf.Tensor 'tower_1/gradients/tower_1/conv1/BiasAdd_grad/tuple/control_dependency_1:0' shape=(16,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0bfbb490>) 
21: (<tf.Tensor 'tower_1/gradients/tower_1/conv2/Conv2D_grad/tuple/control_dependency_1:0' shape=(45, 4, 16, 16) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0bfda950>) 
22: (<tf.Tensor 'tower_1/gradients/tower_1/conv2/BiasAdd_grad/tuple/control_dependency_1:0' shape=(16,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0bf91bd0>) 
23: (<tf.Tensor 'tower_1/gradients/tower_1/conv3/Conv2D_grad/tuple/control_dependency_1:0' shape=(45, 4, 16, 32) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0bfcb590>) 
24: (<tf.Tensor 'tower_1/gradients/tower_1/conv3/BiasAdd_grad/tuple/control_dependency_1:0' shape=(32,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0bf39e90>) 
25: (<tf.Tensor 'tower_1/gradients/tower_1/conv4/Conv2D_grad/tuple/control_dependency_1:0' shape=(45, 4, 32, 64) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0bf499d0>) 
26: (<tf.Tensor 'tower_1/gradients/tower_1/conv4/BiasAdd_grad/tuple/control_dependency_1:0' shape=(64,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0bf14fd0>) 
27: (<tf.Tensor 'tower_1/gradients/tower_1/conv5/Conv2D_grad/tuple/control_dependency_1:0' shape=(45, 4, 64, 128) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0bf39150>) 
28: (<tf.Tensor 'tower_1/gradients/tower_1/conv5/BiasAdd_grad/tuple/control_dependency_1:0' shape=(128,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0bebd8d0>) 
29: (<tf.Tensor 'tower_1/gradients/tower_1/conv6/Conv2D_grad/tuple/control_dependency_1:0' shape=(45, 4, 128, 256) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0bf23110>) 
30: (<tf.Tensor 'tower_1/gradients/tower_1/conv6/BiasAdd_grad/tuple/control_dependency_1:0' shape=(256,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0bf04610>) 
31: (<tf.Tensor 'tower_1/gradients/tower_1/fc1/MatMul_grad/tuple/control_dependency_1:0' shape=(18944, 4096) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0bebdc50>) 
32: (<tf.Tensor 'tower_1/gradients/tower_1/fc1/add_grad/tuple/control_dependency_1:0' shape=(4096,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0bebd310>) 
33: (<tf.Tensor 'tower_1/gradients/tower_1/fc1_1/MatMul_grad/tuple/control_dependency_1:0' shape=(4096, 1024) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0be96e10>) 
34: (<tf.Tensor 'tower_1/gradients/tower_1/fc1_1/add_grad/tuple/control_dependency_1:0' shape=(1024,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0be96990>) 
35: (<tf.Tensor 'tower_1/gradients/tower_1/softmax_linear/MatMul_grad/tuple/control_dependency_1:0' shape=(1024, 360) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0be52c90>) 
36: (<tf.Tensor 'tower_1/gradients/tower_1/softmax_linear/softmax_linear_grad/tuple/control_dependency_1:0' shape=(360,) dtype=float32>, <tensorflow.python.ops.variables.Variable object at 0x7fca0bf56f50>) 

我想知道如何從第二個刪除第一個無，但沒有目標索引，所以我可以爲更多的塔。

Answer 1

我已經找到了錯誤。我正在使用一個可訓練的變量來獲取學習速度（我想trak lr，但看起來不太可能），並且還添加了由adam在op上計算的變量列表。我不確定這是否是一種正確的方式，但它看起來像是有效的。

with tf.Graph().as_default(), tf.device('/cpu:0'): 
     devs = ['/job:prs/task:0/gpu:0','/job:worker/task:0/gpu:0'] # 
     global_step = tf.get_variable('global_step', [], initializer=tf.constant_initializer(0), trainable=False) 
     num_batches_per_epoch = dt_fdr.FLS_PER_ANGLE/ FLAGS.batch_size 
     #lr = tf.Variable(tf.constant(FLAGS.learning_rate, dtype=tf.float32)) 
     opt = tf.train.AdamOptimizer(FLAGS.learning_rate) 
     tower_grads = [] 
     for i in xrange(FLAGS.num_gpus): 
      with tf.device(devs[i]): 
       with tf.name_scope('%s_%d' % (tf_model.TOWER_NAME, i)) as scope: 
        loss = tower_loss(scope) 
        tf.get_variable_scope().reuse_variables() 
        summaries = tf.get_collection(tf.GraphKeys.SUMMARIES, scope) 
        #"print('\n'.join('{}: {}'.format(*k) for k in enumerate(summaries))) 
        grads = opt.compute_gradients(loss, tf.get_collection(tf.GraphKeys.TRAINABLE_VARIABLES, scope)) 
        #print('\n'.join('{}: {}'.format(*k) for k in enumerate(grads))) 
        tower_grads.append(grads) 
     grads = average_gradients(tower_grads) 
     #summaries.append(tf.scalar_summary('learning_rate', lr)) 
     for grad, var in grads: 
      if grad: 
       summaries.append(
        tf.histogram_summary(var.op.name + '/gradients', grad)) 
     apply_gradient_op = opt.apply_gradients(grads, global_step=global_step) 
     for var in tf.trainable_variables(): 
      summaries.append(tf.histogram_summary(var.op.name, var)) 

     train_op = apply_gradient_op 

     saver = tf.train.Saver(tf.all_variables()) 

     summary_op = tf.merge_summary(summaries) 

     init = tf.initialize_all_variables() 

     sess = tf.Session("grpc://nelson-lab:2500",config=tf.ConfigProto(
      allow_soft_placement=True, 
      log_device_placement=FLAGS.log_device_placement)) 
     sess.run(init) 

我不知道是否有人也嘗試使用亞當做一些雙gpu訓練。

問候

Answer 2

附加

如果你有一個計劃，以更新訓練階段學習速率，聲明如下圖所示。

lr = tf.Variable(FLAGS.learning_rate, trainable=False) 
opt = tf.train.AdamOptimizer(lr) 

是

sess.run(tf.assign(lr, new_lr))