File size: 4,557 Bytes
370453e
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
# T5 Comparisons



## Data

Using OpenWebText https://huggingface.co/datasets/openwebtext

```
from datasets import load_dataset
dataset = load_dataset("openwebtext", split='train')
dataset = load_dataset("stas/openwebtext-10k", split='train')
```


Megatron-LM t5 uses a subword-tokenized vocab from bert.

Ready datasets:

1. HF datasets use:

   * `openwebtext` - 8M records `--dataset_name "openwebtext"`
   * `stas/openwebtext-10k` - 10K records `--dataset_name "stas/openwebtext-10k"`

2. Jsonlines (derived):

   * `$six_ALL_CCFRWORK/datasets-custom/openwebtext/openwebtext.jsonl`
   * `$six_ALL_CCFRWORK/datasets-custom/openwebtext-10k/openwebtext-10k.jsonl`

3. Megatron-preprocessed datasets (derived):

   * `$six_ALL_CCFRWORK/datasets-custom/openwebtext/meg-t5_text_document.*`
   * `$six_ALL_CCFRWORK/datasets-custom/openwebtext-10k/meg-t5_text_document.*`

4. Vocabs (from HF):

   * `$six_ALL_CCFRWORK/datasets-custom/vocabs/bert-large-uncased-vocab.txt`


#### How the above was done


For HF datasets and Jsonlines creation details, see [gpt2.md](./gpt2.md). We only need to create the differently pre-processed datasets here.

t5 uses the same tokenizer/indexer as bert - can use it for either t5 or bert meg-lm trainings

Get uncased bert vocab:
```
cd $six_ALL_CCFRWORK/datasets-custom/vocabs
wget https://huggingface.co/bert-large-uncased/resolve/main/vocab.txt -O bert-large-uncased-vocab.txt
```


To prep a 10k-sample for megatron
```
source $six_ALL_CCFRWORK/start-prod
cd $six_ALL_CCFRWORK/code/megatron-lm
python tools/preprocess_data.py \
       --input $six_ALL_CCFRWORK/datasets-custom/openwebtext-10k/openwebtext-10k.jsonl \
       --output-prefix $six_ALL_CCFRWORK/datasets-custom/openwebtext-10k/meg-t5 \
       --vocab $six_ALL_CCFRWORK/datasets-custom/vocabs/bert-large-uncased-vocab.txt \
       --dataset-impl mmap \
       --tokenizer-type BertWordPieceLowerCase \
       --split-sentences \
       --workers 8
```

To prep a full dataset for megatron
```
source $six_ALL_CCFRWORK/start-prod
cd $six_ALL_CCFRWORK/code/megatron-lm
python tools/preprocess_data.py \
       --input $six_ALL_CCFRWORK/datasets-custom/openwebtext-10k/openwebtext.jsonl \
       --output-prefix $six_ALL_CCFRWORK/datasets-custom/openwebtext-10k/meg-t5 \
       --vocab $six_ALL_CCFRWORK/datasets-custom/vocabs/bert-large-uncased-vocab.txt \
       --dataset-impl mmap \
       --tokenizer-type BertWordPieceLowerCase \
       --split-sentences \
       --workers 8

```
as it should take a few hours to convert, use `slurm/jsonl-to-meg-t5.slurm` job to complete it
```
sbatch jsonl-to-meg-t5.slurm
```




## Training

### Megatron-LM distributed with MP

Pipeline Parallelism is not yet support for T5 (in works)

Setup: 1 node / 4 gpus
```
srun --pty --nodes=1 --ntasks=1 --cpus-per-task=40 --gres=gpu:4 --hint=nomultithread --time=60 bash --rcfile $six_ALL_CCFRWORK/start-prod
```

```
cd $six_ALL_CCFRWORK/code/megatron-lm

GPUS_PER_NODE=4

# Change for multinode config
MASTER_ADDR=localhost
MASTER_PORT=6000
NNODES=1
NODE_RANK=0
WORLD_SIZE=$(($GPUS_PER_NODE*$NNODES))

VOCAB_FILE=$six_ALL_CCFRWORK/datasets-custom/vocabs/bert-large-uncased-vocab.txt
DATA_PATH=$six_ALL_CCFRWORK/datasets-custom/openwebtext-10k/meg-t5_text_sentence
SAVE_CHECKPOINT_PATH=$six_ALL_CCFRWORK/checkpoints/t5

DISTRIBUTED_ARGS=" \
    --nproc_per_node $GPUS_PER_NODE \
    --nnodes $NNODES \
    --node_rank $NODE_RANK \
    --master_addr $MASTER_ADDR \
    --master_port $MASTER_PORT \
    "

# from t5 training:
#   --global-batch-size 2048 \
GPT_ARGS=" \
    --num-layers 12 \
    --hidden-size 768 \
    --num-attention-heads 12 \
    --kv-channels 64 \
    --ffn-hidden-size 3072 \
    --encoder-seq-length 512 \
    --decoder-seq-length 128 \
    --micro-batch-size 16 \
    --max-position-embeddings 512 \
    --train-iters 1000000 \
    --lr-decay-iters 1000000 \
    --lr 0.0001 \
    --min-lr 0.00001 \
    --lr-decay-style linear \
    --lr-warmup-fraction .01 \
    --weight-decay 1e-2 \
    --clip-grad 1.0 \
    --fp16 \
    "

OUTPUT_ARGS=" \
    --log-interval 10 \
    --save-interval 500 \
    --eval-interval 100 \
    --eval-iters 10 \
    "

python -m torch.distributed.launch \
    $DISTRIBUTED_ARGS \
    pretrain_t5.py \
    --tensor-model-parallel-size 2 \
    $GPT_ARGS \
    $OUTPUT_ARGS \
    --save $SAVE_CHECKPOINT_PATH \
    --load $SAVE_CHECKPOINT_PATH \
    --data-path $DATA_PATH \
    --data-impl mmap \
    --vocab-file $VOCAB_FILE \
    --vocab-extra-ids 100 \
    --split 949,50,1 \
    --distributed-backend nccl



```