报错信息处理¶
本节内容将介绍使用动态图转静态图(下文简称:动转静)功能发生异常时,ProgramTranslator的动转静报错模块对报错信息做的处理,以帮助您更好地理解动转静报错信息。使用动转静功能运行动态图代码时,内部可以分为2个步骤:动态图代码转换成静态图代码,运行静态图代码。接下来将分别介绍这2个步骤中的异常报错情况。
动转静过程中的异常¶
在动态图代码转换成静态图代码的过程中,如果 ProgramTranslator 无法转换一个函数时,将会显示警告信息,并尝试直接运行该函数。 如下代码中,函数 inner_func
在调用前被转换成静态图代码,当 x = inner_func(data)
调用该函数时,不能重复转换,会给出警告信息:
import paddle
import numpy as np
@paddle.jit.to_static
def func():
def inner_func(x):
x_tensor = paddle.to_tensor(x)
return x_tensor
data = np.ones([3]).astype("int32")
x = inner_func(data)
return x
func()
ProgramTranslator 打印的警告信息如下:
2020-01-01 00:00:00,104-WARNING: <function inner_func at 0x125b3a550> doesn't have to be transformed to static function because it has been transformed before, it will be run as-is.
运行转换后的代码报错¶
如果在动转静后的静态图代码中发生异常,ProgramTranslator 会捕获该异常,增强异常报错信息,将静态图代码报错行映射到转换前的动态图代码,并重新抛出该异常。 重新抛出的异常具有以下特点:
隐藏了部分对用户无用的动转静过程调用栈;
转换后的代码的异常信息,给出提示"In transformed code:";
报错信息中包含了转换前的原始动态图代码,并给出提示"(* user code *)";
例如,运行以下代码,在静态图构建时,即编译期会抛出异常:
import paddle
import numpy as np
@paddle.jit.to_static
def func(x):
x = paddle.to_tensor(x)
x = paddle.reshape(x, shape=[-1, -1])
return x
func(np.ones([3, 2]))
运行结果:
Traceback (most recent call last):
<ipython-input-13-f9c3ea702e3a> in <module>()
func(np.ones([3, 2]))
File "paddle/fluid/dygraph/dygraph_to_static/program_translator.py", line 352, in __call__
error_data.raise_new_exception()
File "paddle/fluid/dygraph/dygraph_to_static/error.py", line 188, in raise_new_exception
raise new_exception
AssertionError: In transformed code:
File "<ipython-input-13-f9c3ea702e3a>", line 7, in func (* user code *)
x = paddle.reshape(x, shape=[-1, -1])
File "paddle/fluid/layers/nn.py", line 6193, in reshape
attrs["shape"] = get_attr_shape(shape)
File "paddle/fluid/layers/nn.py", line 6169, in get_attr_shape
"be -1. But received shape[%d] is also -1." % dim_idx)
AssertionError: Only one dimension value of 'shape' in reshape can be -1. But received shape[1] is also -1.
上述报错信息可以分为3点:
报错栈中,涉及代码转换过程的信息栈默认会被隐藏,不进行展示,以减少干扰信息。
ProgramTranslator 处理后的报错信息中,会包含提示 "In transformed code:",表示之后的报错信息栈,是在运行转换后的代码时的报错信息:
AssertionError: In transformed code: File "<ipython-input-13-f9c3ea702e3a>", line 7, in func (* user code *) x = paddle.reshape(x, shape=[-1, -1]) File "paddle/fluid/layers/nn.py", line 6193, in reshape attrs["shape"] = get_attr_shape(shape) File "paddle/fluid/layers/nn.py", line 6169, in get_attr_shape "be -1. But received shape[%d] is also -1." % dim_idx)
其中,
File "<ipython-input-13-f9c3ea702e3a>", line 7, in func
是转换前的代码位置信息,x = paddle.reshape(x, shape=[-1, -1])
是转换前用户的动态图代码。新的异常中,包含原始报错中的的报错信息,如下:
AssertionError: Only one dimension value of 'shape' in reshape can be -1. But received shape[1] is also -1.
注解:
如果您想查看 Paddle 原生报错信息栈,即未被动转静模块处理过的报错信息栈,可以设置环境变量
TRANSLATOR_DISABLE_NEW_ERROR=1
关闭动转静报错模块。该环境变量默认值为0,表示默认开启动转静报错模块。
运行以下代码,在静态图运行期会抛出异常:
@paddle.jit.to_static
def func(x):
x = paddle.to_tensor(x)
two = paddle.full(shape=[1], fill_value=2, dtype="int32")
x = paddle.reshape(x, shape=[1, two])
return x
func(np.ones([3]).astype("int32"))
运行结果:
Traceback (most recent call last):
File "<ipython-input-57-c63d6a351262>", line 10, in <module>()
func(np.ones([3]).astype("int32"))
File "paddle/fluid/dygraph/dygraph_to_static/program_translator.py", line 352, in __call__
error_data.raise_new_exception()
File "paddle/fluid/dygraph/dygraph_to_static/error.py", line 188, in raise_new_exception
raise new_exception
EnforceNotMet: In transformed code:
File "<ipython-input-57-c63d6a351262>", line 7, in func
x = paddle.reshape(x, shape=[1, two])
File "paddle/tensor/manipulation.py", line 1347, in reshape
return paddle.fluid.layers.reshape(x=x, shape=shape, name=name)
File "paddle/fluid/layers/nn.py", line 6209, in reshape
"XShape": x_shape})
File "paddle/fluid/layer_helper.py", line 43, in append_op
return self.main_program.current_block().append_op(*args, **kwargs)
File "paddle/fluid/framework.py", line 2880, in append_op
attrs=kwargs.get("attrs", None))
File "paddle/fluid/framework.py", line 1977, in __init__
for frame in traceback.extract_stack():
InvalidArgumentError: The 'shape' in ReshapeOp is invalid. The input tensor X'size must be equal to the capacity of 'shape'. But received X's shape = [3], X's size = 3, 'shape' is [1, 2], the capacity of 'shape' is 2.
[Hint: Expected capacity == in_size, but received capacity:2 != in_size:3.] (at /home/teamcity/work/ef54dc8a5b211854/paddle/fluid/operators/reshape_op.cc:222)
[Hint: If you need C++ stacktraces for debugging, please set `FLAGS_call_stack_level=2`.]
[operator < reshape2 > error] [operator < run_program > error]
上述异常中,除了隐藏部分报错栈、报错定位到转换前的动态图代码外,报错信息中隐藏了C++报错栈,您可设置环境变量 FLAGS_call_stack_level=2
来展示 C++ 栈信息。
注解:
如果您想查看被隐藏的信息栈,可以设置环境变量
TRANSLATOR_SIMPLIFY_NEW_ERROR=0
。该环境变量默认值为1,表示隐藏冗余的报错信息栈。