Enable universal checkpoint for zero stage 1 (microsoft#4516)

* Enable uni_ckpt for z1

* Remove logging fix to seperate PR. Relocate conversion script to avoid logging circular import issue

* Formatting fix

* PR feedback

* Handle replicated params

* Detect bf16_optimizer

* Docs

* Fix docs

deepspeed/checkpoint/constants.py

@@ -21,6 +21,7 @@
 ZERO_STAGE = 'zero_stage'
 CLIP_GRAD = 'clip_grad'
 FP32_WEIGHT_KEY = "fp32"
+LOSS_SCALER = 'loss_scaler'
 
 #########################################
 # Module checkpoint keys
@@ -69,3 +70,4 @@
 PIPELINE_REPLICATED_PARAMETER_PATTERNS = 'pipeline_replicated_parameter_patterns'
 PARAMETER_TO_AVERAGE_PATTERNS = 'parameter_to_average_patterns'
 PARAMETER_WITH_ROW_PARALLELISM_PATTERNS = 'parameter_with_row_parallelism_patterns'
+TP_REPLICATED_PARAMETER_PATTERNS = 'tp_replicated_parameter_patterns'

deepspeed/checkpoint/ds_to_universal.py

@@ -0,0 +1,303 @@
+#!/usr/bin/env python
+
+# Copyright (c) Microsoft Corporation.
+# SPDX-License-Identifier: Apache-2.0
+
+# DeepSpeed Team
+
+from functools import partial
+import argparse
+import glob
+import itertools
+import multiprocessing
+import os
+import re
+import shutil
+import torch
+import tqdm
+# from pprint import pprint
+
+from deepspeed.checkpoint import DeepSpeedCheckpoint
+from deepspeed.checkpoint import (
+    OPTIMIZER_STATE_DICT,
+    BASE_OPTIMIZER_STATE,
+    SINGLE_PARTITION_OF_FP32_GROUPS,
+    PARAM_SLICE_MAPPINGS,
+    PARAM_SHAPES,
+    PARAM,
+    CAT_DIM,
+    VOCAB_DIVISIBILITY_PADDING_TENSOR,
+    ORIGINAL_VOCAB_SIZE,
+    UNIVERSAL_CHECKPOINT_INFO,
+    VOCABULARY_PARAMETER_PATTERNS,
+    PIPELINE_REPLICATED_PARAMETER_PATTERNS,
+    TP_REPLICATED_PARAMETER_PATTERNS,
+    PARAMETER_TO_AVERAGE_PATTERNS,
+    PARAMETER_WITH_ROW_PARALLELISM_PATTERNS,
+)
+
+
+def parse_arguments():
+    parser = argparse.ArgumentParser()
+    parser.add_argument('--input_folder', type=str, required=True, help='Input DeepSpeed Checkpoint folder')
+    parser.add_argument('--output_folder', type=str, required=True, help='Output DeepSpeed checkpoint folder')
+    parser.add_argument('--num_extract_workers',
+                        default=4,
+                        type=int,
+                        help='How many parallel processes to extract zero shards')
+    parser.add_argument(
+        '--num_merge_workers',
+        default=2,
+        type=int,
+        help=
+        'How many parallel processes to merge tp slices (more memory intensive, use much fewer than --num_extract_workers))'
+    )
+    parser.add_argument('--keep_temp_folder',
+                        action='store_true',
+                        help='Preserve temporary folder of intermediate checkpoint slice files. Useful for debugging.')
+    args = parser.parse_args()
+    print(f'args = {args}')
+    return args
+
+
+def _create_checkpoint_paths(base_folder, iteration, tp_degree, pp_degree):
+    path_list = []
+    iter_folder = f'iter_{iteration:07d}'
+    for i in range(0, tp_degree):
+        path_list.append([])
+        for j in range(0, pp_degree):
+            rank_folder = f'mp_rank_{i:02d}' if pp_degree == 1 else f'mp_rank_{i:02d}_{j:03d}'
+            ckpt_path = os.path.join(rank_folder, 'model_optim_rng.pt')
+            path_list[i].append(os.path.join(base_folder, iter_folder, ckpt_path))
+
+    return path_list
+
+
+def _save_checkpoint(file_path, chkpt_sd):
+    dir, _ = os.path.split(file_path)
+    os.makedirs(dir, exist_ok=True)
+    torch.save(chkpt_sd, file_path)
+
+
+def extract_zero_shards(dir, ds_checkpoint, indices_3D):
+    pp_index, tp_index, dp_index = indices_3D
+    sd = ds_checkpoint.get_zero_checkpoint_state(pp_index=pp_index, tp_index=tp_index, dp_index=dp_index)
+
+    # pprint(f"Processing {dp_index=} {pp_index=}, {tp_index=}")
+
+    optim_sd = sd[OPTIMIZER_STATE_DICT]
+    param_slice_mappings = optim_sd[PARAM_SLICE_MAPPINGS]
+    universal_checkpoint_info = ds_checkpoint.get_checkpoint_info(UNIVERSAL_CHECKPOINT_INFO)
+    pipeline_replicated_params = universal_checkpoint_info.get(PIPELINE_REPLICATED_PARAMETER_PATTERNS, [])
+    # print(f'{pipeline_replicated_params=}')
+
+    # dict
+    state_groups = optim_sd[BASE_OPTIMIZER_STATE]["state"]
+    # list
+    fp32_groups = optim_sd[SINGLE_PARTITION_OF_FP32_GROUPS]
+    param_groups_cnt = len(state_groups)
+
+    for param_group_id in range(param_groups_cnt):
+
+        flat_state = dict(
+            exp_avg=state_groups[param_group_id]["exp_avg"],
+            exp_avg_sq=state_groups[param_group_id]["exp_avg_sq"],
+            fp32=fp32_groups[param_group_id],
+        )
+
+        for name, fragment_mapping in param_slice_mappings[param_group_id].items():
+            if pp_index > 0 and any(re.match(pattern, name) for pattern in pipeline_replicated_params):
+                # Skip tied weights that are replicated in first and last pp stages
+                continue
+
+            # pprint(f"dpt{dp_index}{pp_index}{tp_index} {param_group_id} {name} => {fragment_mapping.start}:{fragment_mapping.numel}")
+            for state_key in flat_state.keys():
+                dump_param_fragment(dir, tp_index, dp_index, state_key, flat_state[state_key], name,
+                                    fragment_mapping.start, fragment_mapping.numel)
+
+
+cnt = 0
+
+
+def dump_param_fragment(dir, tp_index, dp_index, state_name, state_flat_tensor, param_name, offset, numel):
+
+    global cnt  # temp hack
+
+    param_base_path = os.path.join(dir, param_name, str(tp_index))
+    os.makedirs(param_base_path, exist_ok=True)
+
+    cnt += 1
+    counter = f"{dp_index:0>2d}"
+
+    path = os.path.join(param_base_path, f"{state_name}.{counter}")
+
+    #print(f"{param_name}: {offset}: {numel} => {path}")
+
+    t = state_flat_tensor.narrow(0, offset, numel).clone()
+    _save_checkpoint(path, t)
+
+
+def _merge_zero_shards(param_base_path, state, tp_degree, slice_shape):
+    slices = []
+    for tp_index in range(tp_degree):
+        prefix_path = os.path.join(param_base_path, str(tp_index), f"{state}")
+        paths = sorted(list(glob.glob(f"{prefix_path}.*")))
+        shards = [torch.load(p) for p in paths]
+        slice = torch.cat(shards, dim=0).reshape(slice_shape)
+        slices.append(slice)
+
+    return slices
+
+
+def _get_vocab_divisibility_padding_tensor(universal_checkpoint_info, padded_vocab_tensor):
+    original_vocab_size = universal_checkpoint_info.get(ORIGINAL_VOCAB_SIZE)
+    if padded_vocab_tensor.shape[0] > original_vocab_size:
+        return padded_vocab_tensor[-1]
+    else:
+        return torch.zeros(padded_vocab_tensor.shape[1])
+
+
+def merge_tp_slices(ds_checkpoint, dir, slice_dir, tp_degree, name_and_shape):
+    name, shape = name_and_shape
+    slice_base_path = os.path.join(slice_dir, name)
+    param_base_path = os.path.join(dir, name)
+
+    universal_checkpoint_info = ds_checkpoint.get_checkpoint_info(UNIVERSAL_CHECKPOINT_INFO)
+    replicated_parameters = universal_checkpoint_info.get(TP_REPLICATED_PARAMETER_PATTERNS, [])
+    parameters_to_average = universal_checkpoint_info.get(PARAMETER_TO_AVERAGE_PATTERNS, [])
+    parameters_with_row_parallelism = universal_checkpoint_info.get(PARAMETER_WITH_ROW_PARALLELISM_PATTERNS, [])
+    vocabulary_parameters = universal_checkpoint_info.get(VOCABULARY_PARAMETER_PATTERNS, [])
+    for state in ("fp32", "exp_avg", "exp_avg_sq"):
+        slices = _merge_zero_shards(slice_base_path, state, tp_degree, shape)
+        final_path = os.path.join(param_base_path, f"{state}.pt")
+
+        #print(f"Expected shape: {shape}")
+        #print(f"Fragment sizes:", list(frag.shape for frag in slices))
+        ckpt_dict = {}
+        if any(re.match(pattern, name) for pattern in replicated_parameters):
+            if len(slices) > 1:
+                assert all([slices[0].equal(other_slice) for other_slice in slices[1:]])
+            param = slices[0]
+            # print(f'replicate {name} using first slice')
+        elif any(re.match(pattern, name) for pattern in parameters_to_average):
+            param = sum(slices) / len(slices)
+            # print(f'merge {name} using average')
+        else:
+            cat_dim = 1 if any(re.match(pattern, name) for pattern in parameters_with_row_parallelism) else 0
+            # print(f"merge {name} with CAT DIM: {cat_dim}")
+            param = torch.cat(slices, dim=cat_dim)
+            ckpt_dict[CAT_DIM] = cat_dim
+
+        if any(re.match(pattern, name) for pattern in vocabulary_parameters):
+            #print(f"Before {param.shape=}")
+            # strip padding
+            #param = _strip_vocab_padding(ds_checkpoint, param)
+            ckpt_dict[VOCAB_DIVISIBILITY_PADDING_TENSOR] = _get_vocab_divisibility_padding_tensor(
+                universal_checkpoint_info, param)
+            #print(f"After {param.shape=}")
+
+        #print(f"Final shape: {param.shape}")
+        ckpt_dict[PARAM] = param
+        _save_checkpoint(final_path, ckpt_dict)
+
+
+def _get_chunks(l, n):
+    for i in range(0, len(l), n):
+        yield l[i:i + n]
+
+
+def _do_parallel_work(do_work, work_chunks, num_workers):
+    pool = multiprocessing.Pool(num_workers)
+    for batch in tqdm.tqdm(work_chunks):
+        pool.map(do_work, batch)
+    pool.close()
+    pool.join()
+
+
+def _extract_zero_shard_files(args, ds_checkpoint, temp_dir):
+    _3d_range_list = list(
+        itertools.product(range(ds_checkpoint.pp_degree), range(ds_checkpoint.tp_degree),
+                          range(ds_checkpoint.dp_degree)))
+    # pprint(f'{_3d_range_list=}')
+    work_chunks = list(_get_chunks(_3d_range_list, args.num_extract_workers))
+    # pprint(f'{work_chunks=}')
+
+    # extract_zero_shards(temp_dir, ds_checkpoint, _3d_range_list[0])
+    do_work = partial(extract_zero_shards, temp_dir, ds_checkpoint)
+    _do_parallel_work(do_work, work_chunks, args.num_extract_workers)
+
+
+def _merge_tp_slice_files(args, ds_checkpoint, slice_shapes, temp_dir):
+    work_chunks = list(_get_chunks(list(slice_shapes.items()), args.num_merge_workers))
+    #pprint(work_chunks)
+    zero_output_folder = os.path.join(args.output_folder, "zero")
+    do_work = partial(merge_tp_slices, ds_checkpoint, zero_output_folder, temp_dir, ds_checkpoint.tp_degree)
+    _do_parallel_work(do_work, work_chunks, args.num_merge_workers)
+
+
+def _save_optimizer_state(args, ds_checkpoint):
+    sharded_states = [BASE_OPTIMIZER_STATE, PARAM_SLICE_MAPPINGS, SINGLE_PARTITION_OF_FP32_GROUPS]
+    sd = ds_checkpoint.get_zero_checkpoint_state(pp_index=0, tp_index=0, dp_index=0)
+
+    optim_sd = sd[OPTIMIZER_STATE_DICT]
+    output_sd = {k: v for k, v in optim_sd.items() if k not in sharded_states}
+    zero_output_folder = os.path.join(args.output_folder, "zero")
+    output_file_path = os.path.join(zero_output_folder, f"optimizer_state.pt")
+    _save_checkpoint(output_file_path, output_sd)
+
+
+def _check_for_required_state(ds_checkpoint):
+    universal_checkpoint_info = ds_checkpoint.get_checkpoint_info(UNIVERSAL_CHECKPOINT_INFO)
+    assert universal_checkpoint_info is not None, f'Required {UNIVERSAL_CHECKPOINT_INFO} state is missing in checkpoint. Verify that client creates this state.'
+
+
+def main():
+    print(f'Convert DeepSpeed Checkpoint to Universal Checkpoint')
+
+    args = parse_arguments()
+    print(f'Converting DeepSpeed checkpoint in {args.input_folder} to Universal checkpoint in {args.output_folder}')
+
+    ds_checkpoint = DeepSpeedCheckpoint(args.input_folder)
+    _check_for_required_state(ds_checkpoint)
+
+    iteration = ds_checkpoint.get_iteration()
+    #_create_latest_file(args.output_folder, iteration)
+    checkpoint_paths = _create_checkpoint_paths(args.output_folder, iteration, ds_checkpoint.tp_degree,
+                                                ds_checkpoint.pp_degree)
+
+    slice_shapes = []
+    for mp_rank_file in ds_checkpoint.mp_rank_files:
+        mp_sd = torch.load(mp_rank_file, map_location=torch.device('cpu'))
+        slice_shapes += mp_sd[PARAM_SHAPES]
+
+    # fix back to normal flat dict, merge duplicates for tp>1
+    slice_shapes = dict((k, v) for d in slice_shapes for k, v in d.items())
+    temp_dir = os.path.join(args.output_folder, 'tmp')
+
+    print('*** 1. Extracting ZeRO fragments')
+    _extract_zero_shard_files(args, ds_checkpoint, temp_dir)
+
+    print('*** 2. Merging slices')
+    _merge_tp_slice_files(args, ds_checkpoint, slice_shapes, temp_dir)
+
+    print('*** 3. Saving common optimizer states')
+    _save_optimizer_state(args, ds_checkpoint)
+
+    if not args.keep_temp_folder:
+        shutil.rmtree(temp_dir, ignore_errors=True)
+
+    # Copy mp* files into output folder
+    for f in glob.glob(os.path.join(args.input_folder, 'mp*')):
+        shutil.copy2(f, args.output_folder)
+
+    # Update latest to output folder
+    checkpoint_root_folder, step_folder = os.path.split(args.output_folder)
+    latest_file = os.path.join(checkpoint_root_folder, 'latest_universal')
+    with open(latest_file, "w") as f:
+        f.write(step_folder)
+
+    print('*** Done!')
+
+
+if __name__ == "__main__":
+    main()

deepspeed/runtime/engine.py

@@ -2758,6 +2758,9 @@ def load_checkpoint(self,
         if self._optimizer_has_ckpt_event_epilogue():
             self.optimizer.checkpoint_event_epilogue()
 
+        if self.load_universal_checkpoint():
+            self.optimizer.update_lp_params()
+
         return load_path, client_states
 
     def _load_checkpoint(self,

deepspeed/runtime/pipe/engine.py

@@ -11,6 +11,7 @@
 from deepspeed.utils import logger, timeit
 from deepspeed.utils.timer import ThroughputTimer
 from deepspeed.accelerator import get_accelerator
+from deepspeed.runtime.bf16_optimizer import BF16_Optimizer
 
 from ..engine import DeepSpeedEngine, MEMORY_OPT_ALLREDUCE_SIZE
 from deepspeed.utils.timer import FORWARD_MICRO_TIMER, FORWARD_GLOBAL_TIMER, BACKWARD_MICRO_TIMER, \
@@ -76,6 +77,8 @@ def __init__(self, has_bool_tensors=False, *super_args, **super_kwargs):
         self.has_bool_tensors = has_bool_tensors
         self.eval_return_logits = False
         self.outputs = None
+        # BF16 Optimizer is hardcoded for fp32 gradient accumulation
+        self.using_bf16_optimizer = type(self.optimizer) == BF16_Optimizer
 
         # used to disable the pipeline all-reduce when used with 1-bit Adam/1-bit LAMB
         self.pipeline_enable_backward_allreduce = True
@@ -260,14 +263,14 @@ def _exec_reduce_tied_grads(self):
 
         weight_group_list = self.module.get_tied_weights_and_groups()
         for weight, group in weight_group_list:
-            grad = weight._hp_grad if self.bfloat16_enabled() else weight.grad
+            grad = weight._hp_grad if self.using_bf16_optimizer else weight.grad
             dist.all_reduce(grad, group=group)
 
     # @timeit
     def _exec_reduce_grads(self):
         self._force_grad_boundary = True
         if self.pipeline_enable_backward_allreduce:
-            if self.bfloat16_enabled():
+            if self.using_bf16_optimizer:
                 # PP+BF16 work for ZeRO Stage 1
                 self._bf16_reduce_grads()
             else:
@@ -759,7 +762,7 @@ def _exec_backward_pass(self, buffer_id):
             part_grad = None
             #print(f'RANK={self.global_rank} BEFORE-BWD restored grad={self.grad_layer[0].size()} {self.grad_layer[1].size()}')
 
-        if self.bfloat16_enabled() and not self.is_last_stage():
+        if self.using_bf16_optimizer and not self.is_last_stage():
             # manually call because we don't call optimizer.backward()
             self.optimizer.clear_lp_grads()
 
@@ -771,7 +774,7 @@ def _exec_backward_pass(self, buffer_id):
         else:
             torch.autograd.backward(tensors=(outputs, ), grad_tensors=(grad_tensors, ))
 
-        if self.bfloat16_enabled() and not self.is_last_stage():
+        if self.using_bf16_optimizer and not self.is_last_stage():
             # manually call because we don't call optimizer.backward()
             self.optimizer.update_hp_grads(clear_lp_grads=False)