def validate(args, trainer, task, epoch_itr, subsets):
"""Evaluate the model on the validation set(s) and return the losses."""
valid_losses = []
for subset in subsets:
# Initialize data iterator
itr = task.get_batch_iterator(
dataset=task.dataset(subset),
max_tokens=args.max_tokens_valid,
max_sentences=args.max_sentences_valid,
max_positions=utils.resolve_max_positions(
task.max_positions(),
trainer.get_model().max_positions(),
),
ignore_invalid_inputs=args.skip_invalid_size_inputs_valid_test,
required_batch_size_multiple=args.required_batch_size_multiple,
seed=args.seed,
num_shards=args.distributed_world_size,
shard_id=args.distributed_rank,
num_workers=args.num_workers,
).next_epoch_itr(shuffle=False)
progress = progress_bar.build_progress_bar(
args,
itr,
epoch_itr.epoch,
prefix='valid on \'{}\' subset'.format(subset),
no_progress_bar='simple')
# reset validation loss meters
for k in ['valid_loss', 'valid_nll_loss']:
meter = trainer.get_meter(k)
if meter is not None:
meter.reset()
extra_meters = collections.defaultdict(lambda: AverageMeter())
for sample in progress:
log_output = trainer.valid_step(sample)
for k, v in log_output.items():
if k in [
'loss', 'nll_loss', 'ntokens', 'nsentences',
'sample_size'
]:
continue
extra_meters[k].update(v)
# log validation stats
stats = get_valid_stats(trainer, args, extra_meters)
for k, meter in extra_meters.items():
stats[k] = meter.avg
progress.print(stats, tag=subset, step=trainer.get_num_updates())
valid_losses.append(stats[args.best_checkpoint_metric].avg if args.
best_checkpoint_metric ==
'loss' else stats[args.best_checkpoint_metric])
return valid_losses
def main(parsed_args):
assert parsed_args.path is not None, '--path required for evaluation!'
utils.import_user_module(parsed_args)
print(parsed_args)
use_cuda = torch.cuda.is_available() and not parsed_args.cpu
task = tasks.setup_task(parsed_args)
# Load ensemble
print('| loading model(s) from {}'.format(parsed_args.path))
models, args = checkpoint_utils.load_model_ensemble(
parsed_args.path.split(':'),
arg_overrides=eval(parsed_args.model_overrides),
task=task,
)
for arg in vars(parsed_args).keys():
if arg not in {
'self_target', 'future_target', 'past_target', 'tokens_per_sample',
'output_size_dictionary', 'add_bos_token',
}:
setattr(args, arg, getattr(parsed_args, arg))
# reduce tokens per sample by the required context window size
args.tokens_per_sample -= args.context_window
task = tasks.setup_task(args)
# Load dataset splits
task.load_dataset(args.gen_subset)
dataset = task.dataset(args.gen_subset)
if args.context_window > 0:
dataset = LMContextWindowDataset(
dataset=dataset,
tokens_per_sample=args.tokens_per_sample,
context_window=args.context_window,
pad_idx=task.source_dictionary.pad(),
)
print('| {} {} {} examples'.format(args.data, args.gen_subset, len(dataset)))
# Optimize ensemble for generation and set the source and dest dicts on the model (required by scorer)
for model in models:
model.make_generation_fast_()
if args.fp16:
model.half()
if use_cuda:
model.cuda()
assert len(models) > 0
print('num. model params: {}'.format(sum(p.numel() for p in models[0].parameters())))
itr = task.get_batch_iterator(
dataset=dataset,
max_tokens=args.max_tokens or 36000,
max_sentences=args.max_sentences,
max_positions=utils.resolve_max_positions(*[
model.max_positions() for model in models
]),
ignore_invalid_inputs=True,
num_shards=args.num_shards,
shard_id=args.shard_id,
num_workers=args.num_workers,
).next_epoch_itr(shuffle=False)
gen_timer = StopwatchMeter()
scorer = SequenceScorer(task.target_dictionary, args.softmax_batch)
score_sum = 0.
count = 0
if args.remove_bpe is not None:
if args.remove_bpe == 'sentencepiece':
raise NotImplementedError
else:
bpe_cont = args.remove_bpe.rstrip()
bpe_toks = set(
i
for i in range(len(task.source_dictionary))
if task.source_dictionary[i].endswith(bpe_cont)
)
bpe_len = len(bpe_cont)
else:
bpe_toks = None
bpe_len = 0
word_stats = dict()
with progress_bar.build_progress_bar(args, itr) as t:
wps_meter = TimeMeter()
for sample in t:
if 'net_input' not in sample:
continue
sample = utils.move_to_cuda(sample) if use_cuda else sample
gen_timer.start()
hypos = scorer.generate(models, sample)
gen_timer.stop(sample['ntokens'])
for hypos_i in hypos:
hypo = hypos_i[0]
tokens = hypo['tokens']
tgt_len = tokens.numel()
pos_scores = hypo['positional_scores'].float()
if args.add_bos_token:
assert hypo['tokens'][0].item() == task.target_dictionary.bos()
tokens = tokens[1:]
pos_scores = pos_scores[1:]
skipped_toks = 0
if bpe_toks is not None:
for i in range(tgt_len - 1):
if tokens[i].item() in bpe_toks:
skipped_toks += 1
pos_scores[i + 1] += pos_scores[i]
pos_scores[i] = 0
inf_scores = pos_scores.eq(float('inf')) | pos_scores.eq(float('-inf'))
if inf_scores.any():
print('| Skipping tokens with inf scores:',
task.target_dictionary.string(tokens[inf_scores.nonzero()]))
pos_scores = pos_scores[(~inf_scores).nonzero()]
score_sum += pos_scores.sum().cpu()
count += pos_scores.numel() - skipped_toks
if args.output_word_probs or args.output_word_stats:
w = ''
word_prob = []
is_bpe = False
for i in range(len(tokens)):
w_ind = tokens[i].item()
w += task.source_dictionary[w_ind]
if bpe_toks is not None and w_ind in bpe_toks:
w = w[:-bpe_len]
is_bpe = True
else:
word_prob.append((w, pos_scores[i].item()))
next_prob = None
ind = i + 1
while ind < len(tokens):
if pos_scores[ind].item() != 0:
next_prob = pos_scores[ind]
break
ind += 1
word_stats.setdefault(w, WordStat(w, is_bpe)).add(pos_scores[i].item(), next_prob)
is_bpe = False
w = ''
if args.output_word_probs:
print('\t'.join('{} [{:2f}]'.format(x[0], x[1]) for x in word_prob))
wps_meter.update(sample['ntokens'])
t.log({'wps': round(wps_meter.avg)})
avg_nll_loss = -score_sum / count
print('| Evaluated {} tokens in {:.1f}s ({:.2f} tokens/s)'.format(gen_timer.n, gen_timer.sum, 1. / gen_timer.avg))
print('| Loss: {:.4f}, Perplexity: {:.2f}'.format(avg_nll_loss, np.exp(avg_nll_loss)))
if args.output_word_stats:
for ws in sorted(word_stats.values(), key=lambda x: x.count, reverse=True):
print(ws)
def train(args, trainer, task, epoch_itr):
"""Train the model for one epoch."""
# Update parameters every N batches
update_freq = args.update_freq[epoch_itr.epoch - 1] \
if epoch_itr.epoch <= len(args.update_freq) else args.update_freq[-1]
# Initialize data iterator
itr = epoch_itr.next_epoch_itr(
fix_batches_to_gpus=args.fix_batches_to_gpus,
shuffle=(epoch_itr.epoch >= args.curriculum),
)
itr = iterators.GroupedIterator(itr, update_freq)
progress = progress_bar.build_progress_bar(
args, itr, epoch_itr.epoch, no_progress_bar='simple',
)
extra_meters = collections.defaultdict(lambda: AverageMeter())
valid_subsets = args.valid_subset.split(',')
max_update = args.max_update or math.inf
for i, samples in enumerate(progress, start=epoch_itr.iterations_in_epoch):
log_output = trainer.train_step(samples)
if log_output is None:
continue
# log mid-epoch stats
stats = get_training_stats(trainer)
for k, v in log_output.items():
if k in ['loss', 'nll_loss', 'ntokens', 'nsentences', 'sample_size']:
continue # these are already logged above
if 'loss' in k or k == 'accuracy':
extra_meters[k].update(v, log_output['sample_size'])
else:
extra_meters[k].update(v)
stats[k] = extra_meters[k].avg
progress.log(stats, tag='train', step=stats['num_updates'])
# ignore the first mini-batch in words-per-second calculation
if i == 0:
trainer.get_meter('wps').reset()
num_updates = trainer.get_num_updates()
if (
not args.disable_validation
and args.save_interval_updates > 0
and num_updates % args.save_interval_updates == 0
and num_updates > 0
):
valid_losses = validate(args, trainer, task, epoch_itr, valid_subsets)
checkpoint_utils.save_checkpoint(args, trainer, epoch_itr, valid_losses[0])
if num_updates >= max_update:
break
# log end-of-epoch stats
stats = get_training_stats(trainer)
for k, meter in extra_meters.items():
stats[k] = meter.avg
progress.print(stats, tag='train', step=stats['num_updates'])
# reset training meters
for k in [
'train_loss', 'train_nll_loss', 'wps', 'ups', 'wpb', 'bsz', 'gnorm', 'clip',
]:
meter = trainer.get_meter(k)
if meter is not None:
meter.reset()
def main(args):
assert args.path is not None, '--path required for generation!'
assert not args.sampling or args.nbest == args.beam, \
'--sampling requires --nbest to be equal to --beam'
assert args.replace_unk is None or args.raw_text, \
'--replace-unk requires a raw text dataset (--raw-text)'
utils.import_user_module(args)
if args.max_tokens is None and args.max_sentences is None:
args.max_tokens = 12000
print(args)
use_cuda = torch.cuda.is_available() and not args.cpu
# Load dataset splits
task = tasks.setup_task(args)
task.load_dataset(args.gen_subset)
# Set dictionaries
try:
src_dict = getattr(task, 'source_dictionary', None)
except NotImplementedError:
src_dict = None
tgt_dict = task.target_dictionary
# Load ensemble
print('| loading model(s) from {}'.format(args.path))
models, _model_args = checkpoint_utils.load_model_ensemble(
args.path.split(':'),
arg_overrides=eval(args.model_overrides),
task=task,
)
# Optimize ensemble for generation
for model in models:
model.make_generation_fast_(
beamable_mm_beam_size=None if args.no_beamable_mm else args.beam,
need_attn=args.print_alignment,
)
if args.fp16:
model.half()
if use_cuda:
model.cuda()
# Load alignment dictionary for unknown word replacement
# (None if no unknown word replacement, empty if no path to align dictionary)
align_dict = utils.load_align_dict(args.replace_unk)
# Load dataset (possibly sharded)
itr = task.get_batch_iterator(
dataset=task.dataset(args.gen_subset),
max_tokens=args.max_tokens,
max_sentences=args.max_sentences,
max_positions=utils.resolve_max_positions(
task.max_positions(),
*[model.max_positions() for model in models]
),
ignore_invalid_inputs=args.skip_invalid_size_inputs_valid_test,
required_batch_size_multiple=args.required_batch_size_multiple,
num_shards=args.num_shards,
shard_id=args.shard_id,
num_workers=args.num_workers,
).next_epoch_itr(shuffle=False)
# Initialize generator
gen_timer = StopwatchMeter()
generator = task.build_generator(args)
# Generate and compute BLEU score
if args.sacrebleu:
scorer = bleu.SacrebleuScorer()
else:
scorer = bleu.Scorer(tgt_dict.pad(), tgt_dict.eos(), tgt_dict.unk())
num_sentences = 0
has_target = True
with progress_bar.build_progress_bar(args, itr) as t:
wps_meter = TimeMeter()
for sample in t:
sample = utils.move_to_cuda(sample) if use_cuda else sample
if 'net_input' not in sample:
continue
prefix_tokens = None
if args.prefix_size > 0:
prefix_tokens = sample['target'][:, :args.prefix_size]
gen_timer.start()
hypos = task.inference_step(generator, models, sample, prefix_tokens)
num_generated_tokens = sum(len(h[0]['tokens']) for h in hypos)
gen_timer.stop(num_generated_tokens)
for i, sample_id in enumerate(sample['id'].tolist()):
has_target = sample['target'] is not None
# Remove padding
src_tokens = utils.strip_pad(sample['net_input']['src_tokens'][i, :], tgt_dict.pad())
target_tokens = None
if has_target:
target_tokens = utils.strip_pad(sample['target'][i, :], tgt_dict.pad()).int().cpu()
# Either retrieve the original sentences or regenerate them from tokens.
if align_dict is not None:
src_str = task.dataset(args.gen_subset).src.get_original_text(sample_id)
target_str = task.dataset(args.gen_subset).tgt.get_original_text(sample_id)
else:
if src_dict is not None:
src_str = src_dict.string(src_tokens, args.remove_bpe)
else:
src_str = ""
if has_target:
target_str = tgt_dict.string(target_tokens, args.remove_bpe, escape_unk=True)
if not args.quiet:
if src_dict is not None:
print('S-{}\t{}'.format(sample_id, src_str))
if has_target:
print('T-{}\t{}'.format(sample_id, target_str))
# Process top predictions
for j, hypo in enumerate(hypos[i][:args.nbest]):
hypo_tokens, hypo_str, alignment = utils.post_process_prediction(
hypo_tokens=hypo['tokens'].int().cpu(),
src_str=src_str,
alignment=hypo['alignment'].int().cpu() if hypo['alignment'] is not None else None,
align_dict=align_dict,
tgt_dict=tgt_dict,
remove_bpe=args.remove_bpe,
)
if not args.quiet:
print('H-{}\t{}\t{}'.format(sample_id, hypo['score'], hypo_str))
print('P-{}\t{}'.format(
sample_id,
' '.join(map(
lambda x: '{:.4f}'.format(x),
hypo['positional_scores'].tolist(),
))
))
if args.print_alignment:
print('A-{}\t{}'.format(
sample_id,
' '.join(map(lambda x: str(utils.item(x)), alignment))
))
# Score only the top hypothesis
if has_target and j == 0:
if align_dict is not None or args.remove_bpe is not None:
# Convert back to tokens for evaluation with unk replacement and/or without BPE
target_tokens = tgt_dict.encode_line(target_str, add_if_not_exist=True)
if hasattr(scorer, 'add_string'):
scorer.add_string(target_str, hypo_str)
else:
scorer.add(target_tokens, hypo_tokens)
wps_meter.update(num_generated_tokens)
t.log({'wps': round(wps_meter.avg)})
num_sentences += sample['nsentences']
print('| Translated {} sentences ({} tokens) in {:.1f}s ({:.2f} sentences/s, {:.2f} tokens/s)'.format(
num_sentences, gen_timer.n, gen_timer.sum, num_sentences / gen_timer.sum, 1. / gen_timer.avg))
if has_target:
print('| Generate {} with beam={}: {}'.format(args.gen_subset, args.beam, scorer.result_string()))
return scorer