pytorch/caffe2/python/layers/sparse_lookup.py
Benny Chen d23d62cb1e Fix unaries to export fp16 instead of fp32 when rest of the model export to int8
Summary: Currently accelerators does not have the concept for fp32, it only has understandings of fp16 and int8 in terms of data input. In order to fixe the issue here, we want to make sure unaries are turned into fp16 when we have the int8 exporter turned on.

Reviewed By: kennyhorror

Differential Revision: D17743791

fbshipit-source-id: 7322d23eb12ac3f813b525fc0ddd066f95c8ca85
2019-10-14 10:51:17 -07:00

556 lines
22 KiB
Python

## @package sparse_lookup
# Module caffe2.python.layers.sparse_lookup
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from __future__ import unicode_literals
from caffe2.python.optimizer import FP16_ENGINES, Optimizer
from caffe2.python.helpers.arg_scope import get_current_scope
from caffe2.python import schema
from caffe2.python.layers.layers import (
get_categorical_limit,
get_key,
IdList,
IdScoreList,
IdListWithEvicted,
IdScoreListWithEvicted,
LayerPsParam,
ModelLayer,
almost_equal_schemas,
)
import collections
import functools
import logging
import math
import numpy as np
import operator
logger = logging.getLogger(__name__)
def get_trainer_version_based_on_optim(optim_def):
if isinstance(optim_def, Optimizer) and hasattr(optim_def, "engine"):
logger.info(
"Attempting to set trainer version for engine {}".format(optim_def.engine)
)
if optim_def.engine in FP16_ENGINES:
logger.info("Setting FP16 trainer for engine {}".format(optim_def.engine))
return "fp16"
else:
logger.info("Setting FP32 trainer for engine {}".format(optim_def.engine))
return "fp32"
else:
return "fp32"
def get_sparse_lookup_predictor_version(
version,
blob_size=None,
min_blob_size_4bits=None,
embedding_dim=None,
sparse_feature_name=None,
):
assert version in {
'fp32', 'fp16', 'uint8rowwise', 'fused_uint8rowwise', 'fused_uint4rowwise'
}, "Unexpected version of sparse_lookup layer {0}".format(version)
if version == 'fused_uint4rowwise':
if (
blob_size is not None
and min_blob_size_4bits is not None
and embedding_dim is not None
):
if blob_size < min_blob_size_4bits:
logger.info(
"{} fall back to uint8 because lookup table size {} < min_blob_size_4bits {}".format(
sparse_feature_name,
blob_size,
min_blob_size_4bits,
)
)
version = 'fused_uint8rowwise'
if embedding_dim % 2 == 1:
logger.info(
"{} fall back to uint8 because lookup table dimension {} is not divisible by 2".format(
sparse_feature_name, embedding_dim
)
)
version = 'fused_uint8rowwise'
else:
raise ValueError(
(
"When 4 bit quantization is enabled for {}, "
"(i.e., Sparse lookup predictor version:{}), "
"requires arguments blob_size:{}, "
"min_blob_size_4bits:{}, embedding_dim:{}"
).format(
sparse_feature_name,
version,
blob_size,
min_blob_size_4bits,
embedding_dim
)
)
return version
def get_sparse_lookup_trainer_version(version):
assert version in {'fp32', 'fp16'},\
"Unexpected version of sparse_lookup layer {0}".format(version)
return version
def _is_id_list(input_record):
return almost_equal_schemas(input_record, IdList)
def _is_id_score_list(input_record):
return almost_equal_schemas(input_record,
IdScoreList,
check_field_types=False)
class SparseLookup(ModelLayer):
_id_list_supported_reducers = [
'LogMeanExp', 'LogSumExp', 'Max', 'Mean', 'Sum',
'WeightedSum', 'WeightedMean', 'Sqrt', 'None']
_id_score_list_supported_reducers = [
'PositionWeighted', 'RecencyWeighted', 'Mean', 'Sum', 'WeightedSum',
'WeightedMean', 'None'
]
_fp16_compatible_init_op_types = [
'Float16UniformFill'
]
_fp16_compatible_reducers = [
'Sum', 'Mean', 'Sqrt', 'PositionWeighted', 'RecencyWeighted',
]
def __init__(self, model, input_record, inner_shape, reducer,
weight_init=None, weight_optim=None,
name='sparse_lookup', regularizer=None, use_external_weights=False, **kwargs):
super(SparseLookup, self).__init__(model, name, input_record, **kwargs)
self.sparse_key = get_key(self.input_record)()
logger.info("Setup the sparse lookup layer for " + self.sparse_key)
# TODO Add some asserts about input type
if isinstance(inner_shape, int):
inner_shape = [inner_shape]
assert isinstance(inner_shape, list) or isinstance(inner_shape, tuple),\
"Unexpected type for inner_shape, expected list or tuple, got {0} for {1}".\
format(type(inner_shape), self.sparse_key)
if reducer == "PositionWeighted":
assert _is_id_score_list(self.input_record), (
"PositionWeighted only support IdScoreList, but got {} for {}"
+ "please use PositionWeighted layer to convert IdList "
+ "to IdScoreList"
).format(repr(self.input_record), self.sparse_key)
self.external_weights = self.input_record.values()
elif reducer == "RecencyWeighted":
assert _is_id_score_list(self.input_record), (
"RecencyWeighted only supports IdScoreList, "
"while the sparse feature {} is not.".format(self.sparse_key)
)
self.external_weights = self.input_record.values()
# TODO: create a new type of reducer with external weights to wrap
# this and the above two cases since essentially their input formats
# are the same.
elif use_external_weights:
assert _is_id_score_list(self.input_record), (
"Use_external_weights only supports IdScoreList, "
"while the sparse feature {} is not.".format(self.sparse_key)
)
assert reducer in ["Sum", "WeightedSum"], (
"Use_external_weights only supports Sum reducer, "
"while the reducer is {}.".format(reducer)
)
self.external_weights = self.input_record.values()
self.reducer = reducer
self.use_external_weights = use_external_weights
input_dim = get_categorical_limit(self.input_record)
assert input_dim > 0, "{} should have categorical limit > 0, but got {}".format(
self.sparse_key, input_dim
)
self.input_dim = input_dim
self.shape = [input_dim] + inner_shape
self.trainer_version = get_trainer_version_based_on_optim(
weight_optim
)
default_init_op = self._get_default_init_op()
self.weight_init = weight_init or default_init_op
self.evicted_values = None
if schema.equal_schemas(
self.input_record, IdListWithEvicted
) or schema.equal_schemas(
self.input_record, IdScoreListWithEvicted, check_field_types=False
):
self.evicted_values = self.input_record._evicted_values
# If fp16 is used, make sure fp16 init op is used
if self.trainer_version == "fp16":
assert self.reducer in self._fp16_compatible_reducers or use_external_weights, (
"Fp16 training is enabled. The reducer specified is not supported. "
"Got {}. Supported reducers: {}. Right now, in general, sum, mean, "
"positional pooling are supported. Attention is not. Please check "
"if there is fp16 trained sparse features using advanced pooling.".format(
self.reducer, self._fp16_compatible_reducers)
)
# if init op is UniformFill, we replace it directly
if self.weight_init[0] == "UniformFill":
self.weight_init = ("Float16UniformFill", self.weight_init[1])
assert self.weight_init[0] in self._fp16_compatible_init_op_types, (
"Fp16 training is enabled. Init op for weight parameter must be fp16 "
"compatibale. Got {}. Supported ops: {}".format(
self.weight_init[0],
self._fp16_compatible_init_op_types)
)
assert regularizer is None, "Regularizer is not compatible with fp16"
if self.input_record.lengths.metadata:
avg_length = self.input_record.lengths.metadata.expected_value
else:
avg_length = None
self.w = self.create_param(
param_name='w',
shape=self.shape,
initializer=self.weight_init,
optimizer=weight_optim,
ps_param=LayerPsParam(
sparse_key=self.sparse_key,
average_length=avg_length),
regularizer=regularizer
)
if self.evicted_values:
self.reinit_vec = self.create_param(
param_name="reinit_vec",
shape=inner_shape,
initializer=self.weight_init,
optimizer=model.NoOptim,
regularizer=None,
)
self.scale_bias_init = ('ConstantFill', {'value': 0.0})
self.scale_bias = self.create_param(
param_name='scale_bias',
shape=[],
initializer=self.scale_bias_init,
optimizer=model.NoOptim,
)
self.output_schema = schema.Scalar(
(np.float32, inner_shape),
self.get_next_blob_reference('output'),
)
def get_memory_usage(self):
return functools.reduce(operator.mul, self.shape) * 4
def get_fp16_compatible_parameters(self):
return [self.w]
def support_8bit(self):
# Rowwise quantization makes sense only if shape it's 2D matrix with
# second dimension >= 8
if len(self.shape) != 2 or self.shape[1] < 8:
return False
return True
def get_8bits_compatible_parameters(self, fused=True):
if not self.support_8bit():
return []
if fused:
RowwiseQuantized8BitsWeight = collections.namedtuple(
'RowwiseQuantized8BitsWeight', 'w'
)
return [RowwiseQuantized8BitsWeight(self.w)]
else:
RowwiseQuantized8BitsWeight = collections.namedtuple(
'RowwiseQuantized8BitsWeight', 'w, scale_bias'
)
return [RowwiseQuantized8BitsWeight(self.w, self.scale_bias)]
def _get_default_init_op(self):
scale = math.sqrt(1.0 / self.input_dim)
if self.trainer_version == 'fp32':
default_weight_init = ('UniformFill', {'min': -scale, 'max': scale})
elif self.trainer_version == 'fp16':
default_weight_init = ("Float16UniformFill", {'min': -scale, 'max': scale})
else:
raise NotImplementedError(
"Train version {} is not currently supported for sparse feature {}".format(
trainer_version, self.sparse_key
)
)
return default_weight_init
def _gather_wrapper(self, net, version, in_indices, out):
# Gather can work on all kinds of input data types, and output
# data with the same type. Convert the output of Gather to float,
# because the follow-up Ops expect fp32.
if version == 'fp32':
return net.Gather([self.w, in_indices], out)
elif version == 'fp16':
gathered_w = net.Gather([self.w, in_indices], 'gathered_w')
return net.HalfToFloat(gathered_w, out)
elif version == 'uint8rowwise':
gathered_w = net.Gather([self.w, in_indices], 'gathered_w')
gathered_scale_bias = net.Gather(
[self.scale_bias, in_indices],
'gathered_scale_bias'
)
return net.Rowwise8BitQuantizedToFloat(
[gathered_w, gathered_scale_bias], out)
elif version == 'fused_uint8rowwise':
gathered_w = net.Gather([self.w, in_indices], 'gathered_w')
return net.Fused8BitRowwiseQuantizedToFloat(gathered_w, out)
elif version == 'fused_uint4rowwise':
gathered_w = net.Gather([self.w, in_indices], 'gathered_w')
return net.Fused4BitRowwiseQuantizedToFloat(gathered_w, out)
else:
raise "Unsupported version of operators in SparseLookup " +\
"layer: {0} for sparse feature {1}".format(
version, self.sparse_key
)
def _sparse_lengths_weighted_reducer(
self,
in_indices,
weights,
reducer,
net,
version,
grad_on_weights=0,
):
op_input = [
self.w,
weights,
in_indices,
self.input_record.lengths(),
]
layer_name = 'SparseLengths' + reducer
if version in ['fp32', 'fp16']:
# SparseLengths* Ops will accept either fp16 or fp32 embedding
# matrix and output fp32 pooled embedding
# A special case here is that we need FP16 engine for
# SparseLengthsWeightedSum when FP16 embeedings are used for
# correct backward updates
if reducer == "WeightedSum" and version == "fp16":
net.SparseLengthsWeightedSum(
op_input,
self.output_schema.field_blobs(),
grad_on_weights=grad_on_weights,
engine='FP16',
)
else:
net.__getattr__(layer_name)(
op_input,
self.output_schema.field_blobs(),
grad_on_weights=grad_on_weights,
)
elif version == 'uint8rowwise':
op_input.insert(len(op_input), self.scale_bias)
net.__getattr__(layer_name + '8BitsRowwise')(
op_input, self.output_schema.field_blobs())
elif version == 'fused_uint8rowwise':
net.__getattr__(layer_name + 'Fused8BitRowwise')(
op_input, self.output_schema.field_blobs())
elif version == 'fused_uint4rowwise':
net.__getattr__(layer_name + 'Fused4BitRowwise')(
op_input, self.output_schema.field_blobs())
else:
raise "Unsupported version of operator in SparseLookUp " +\
"layer: {0} for sparse feature {1}".format(
version, self.sparse_key
)
# deal with sparse features of id_list type
def _add_ops_id_list(self, net, version):
assert self.reducer in self._id_list_supported_reducers, (
"Unsupported reducer: {} for ID_LIST {}".format(
self.reducer, self.sparse_key
)
)
if self.reducer in ['Sum', 'Mean', 'WeightedSum', 'WeightedMean']:
op_input = [self.w,
self.input_record.items(),
self.input_record.lengths()]
# For id list features, the behaviors of 'Sum' and
# 'WeightedSum' are identical, since we can regard the weight on each
# id as 1. Similarly, for 'Mean' and 'WeightedMean'.
if self.reducer == 'WeightedSum':
self.reducer = 'Sum'
elif self.reducer == 'WeightedMean':
self.reducer = 'Mean'
layer_name = 'SparseLengths' + self.reducer
if version in ['fp32', 'fp16']:
# SparseLengths* Ops will accept either fp16 or fp32 embedding
# matrix and output fp32 pooled embedding
net.__getattr__(layer_name)(
op_input,
self.output_schema.field_blobs(),
)
elif version == 'uint8rowwise':
op_input.insert(len(op_input), self.scale_bias)
net.__getattr__(layer_name + '8BitsRowwise')(
op_input, self.output_schema.field_blobs())
elif version == 'fused_uint8rowwise':
net.__getattr__(layer_name + 'Fused8BitRowwise')(
op_input, self.output_schema.field_blobs())
elif version == 'fused_uint4rowwise':
net.__getattr__(layer_name + 'Fused4BitRowwise')(
op_input, self.output_schema.field_blobs())
else:
raise "Unsupported version of operator in SparseLookUp " +\
"layer: {0} for sparse feature {1}".format(
version, self.sparse_key
)
elif self.reducer == 'Sqrt':
sqrt_weight = net.LengthsToWeights(
[self.input_record.lengths()],
[net.NextScopedBlob('lengths_sqrt')],
power=0.5,
)
self._sparse_lengths_weighted_reducer(
self.input_record.items(),
sqrt_weight,
'WeightedSum', net, version)
elif self.reducer == 'None':
# Gather operator will gather the embedding for each id of
# each IdList.
self._gather_wrapper(net, version, self.input_record.items(),
self.output_schema.field_blobs())
else:
table_rows = self._gather_wrapper(
net, version, self.input_record.items(), 'table_rows')
segment_ids = net.LengthsToSegmentIds(
self.input_record.lengths(),
net.NextScopedBlob(self.input_record.lengths() + '_sid'))
net.__getattr__('SortedSegmentRange' + self.reducer)(
[table_rows, segment_ids],
self.output_schema.field_blobs(),
)
# deal with sparse features of id_score_list type
def _add_ops_id_score_list(self, net, version):
assert self.reducer in self._id_score_list_supported_reducers, (
"Unsupported reducer: {} for ID_SCORE_LIST {}".format(
self.reducer, self.sparse_key
)
)
if self.reducer in ['WeightedSum', 'WeightedMean']:
self._sparse_lengths_weighted_reducer(
self.input_record.keys(),
self.input_record.values(),
self.reducer, net, version)
elif self.reducer in ['PositionWeighted', 'RecencyWeighted'] or self.use_external_weights:
self._sparse_lengths_weighted_reducer(
self.input_record.keys(),
self.external_weights,
'WeightedSum', net, version, grad_on_weights=1)
elif self.reducer in ['Sum', 'Mean']:
op_input = [self.w,
self.input_record.keys(),
self.input_record.lengths()]
layer_name = 'SparseLengths' + self.reducer
if version in ['fp32', 'fp16']:
net.__getattr__(layer_name)(
op_input,
self.output_schema.field_blobs(),
)
elif version == 'uint8rowwise':
net.__getattr__(layer_name + '8BitsRowwise')(
op_input, self.output_schema.field_blobs())
elif version == 'fused_uint8rowwise':
net.__getattr__(layer_name + 'Fused8BitRowwise')(
op_input, self.output_schema.field_blobs())
elif version == 'fused_uint4rowwise':
net.__getattr__(layer_name + 'Fused4BitRowwise')(
op_input, self.output_schema.field_blobs())
else:
raise "Unsupported version of operator in SparseLookUp " +\
"layer: {0} for sparse feature {1}".format(
version, self.sparse_key
)
elif self.reducer == 'None':
# Gather operator will gather the embedding for each id of
# each IdList.
self._gather_wrapper(net, version, self.input_record.keys(),
self.output_schema.field_blobs())
else:
raise "Only Sum, Mean, None are supported for IdScoreList input." +\
"Trying to create with {} for sparse feature {}".format(
self.reducer, self.sparse_key
)
def _add_ops(self, net, version='fp32'):
if self.evicted_values:
net.CopyRowsToTensor(
[self.w, self.evicted_values.get(), self.reinit_vec], [self.w])
if _is_id_list(self.input_record):
self._add_ops_id_list(net, version=version)
elif _is_id_score_list(self.input_record):
self._add_ops_id_score_list(net, version=version)
else:
raise "Unsupported input type {0}".format(self.input_record)
def add_train_ops(self, net):
self._add_ops(net, self.trainer_version)
def add_ops(self, net):
version_info = get_current_scope().get(
get_sparse_lookup_predictor_version.__name__, {'version': 'fp32'}
)
lookup_table_blob_size = self.shape[0] * self.shape[1]
version = get_sparse_lookup_predictor_version(
version_info['version'],
blob_size=lookup_table_blob_size,
min_blob_size_4bits=(
version_info['min_blob_size_4bits']
if 'min_blob_size_4bits' in version_info
else None
),
embedding_dim=self.shape[1],
sparse_feature_name=self.sparse_key,
)
# TODO(amalevich): Layer should not be responsible for decision about
# quantization.
if not self.support_8bit() and version in {'uint8rowwise',
'fused_uint8rowwise',
'fused_uint4rowwise'}:
version = 'fp16'
self._add_ops(net, version)