我正在使用Hyperopt对神经网络进行超参数优化。这样做时,经过一些迭代,我得到了MemoryError异常

到目前为止,我尝试清除所有已使用过的变量(为它们分配无值或空列表,是否有更好的方法呢?)并打印所有locals(),dirs()和globals()及其大小,但是这些数量永远不会增加,而且尺寸很小。

结构如下:

def create_model(params):
    ## load data from temp files
    ## pre-process data accordingly
    ## Train NN with crossvalidation clearing Keras' session every time
    ## save stats and clean all variables (assigning None or empty lists to them)

def Optimize():
    for model in models: #I have multiple models
        ## load data
        ## save data to temp files
        trials = Trials()
        best_run = fmin(create_model,
                        space,
                        algo=tpe.suggest,
                        max_evals=100,
                        trials=trials)



在X次迭代之后(有时它完成了前100次并转移到第二个模型),它引发了内存错误。
我的猜测是某些变量仍保留在内存中,我没有清除它们,但是我无法检测到它们。

编辑:

Traceback (most recent call last):
  File "Main.py", line 32, in <module>
    optimal = Optimize(training_sets)
  File "/home/User1/Optimizer/optimization2.py", line 394, in Optimize
    trials=trials)
  File "/usr/local/lib/python3.5/dist-packages/hyperopt/fmin.py", line 307, in fmin
    return_argmin=return_argmin,
  File "/usr/local/lib/python3.5/dist-packages/hyperopt/base.py", line 635, in fmin
    return_argmin=return_argmin)
  File "/usr/local/lib/python3.5/dist-packages/hyperopt/fmin.py", line 320, in fmin
    rval.exhaust()
  File "/usr/local/lib/python3.5/dist-packages/hyperopt/fmin.py", line 199, in exhaust
    self.run(self.max_evals - n_done, block_until_done=self.async)
  File "/usr/local/lib/python3.5/dist-packages/hyperopt/fmin.py", line 173, in run
    self.serial_evaluate()
  File "/usr/local/lib/python3.5/dist-packages/hyperopt/fmin.py", line 92, in serial_evaluate
    result = self.domain.evaluate(spec, ctrl)
  File "/usr/local/lib/python3.5/dist-packages/hyperopt/base.py", line 840, in evaluate
    rval = self.fn(pyll_rval)
  File "/home/User1/Optimizer/optimization2.py", line 184, in create_model
    x_train, x_test = x[train_indices], x[val_indices]
MemoryError

最佳答案

我花了几天的时间解决了这个问题,所以我将回答自己的问题,以节省遇到此问题的任何人。

通常,将Hyperopt用于Keras时,return函数的建议create_model如下所示:

return {'loss': -acc, 'status': STATUS_OK, 'model': model}


但是在具有许多评估的大型模型中,您不想返回每个模型并将其保存在内存中,您所需要做的只是提供给出最低loss的超参数集

通过简单地从返回的字典中删除模型,解决了每次评估时内存增加的问题。

return {'loss': -acc, 'status': STATUS_OK}

关于python - 如何在Python中找到MemoryError的来源?,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/55678552/

10-12 18:32