Seeking a good multi-node training config

Comienza con el script de lanzamiento multi-node del issue y el punto de entrada pretrain_gpt.py referenciado. Reproduce la ejecución en dos nodos e inspecciona la configuración de distributed, MoE y comunicación mientras comparas el tiempo de iteración. Se considera terminado cuando se documenta una configuración multi-node validada o se proporciona un script de entrenamiento completo que aborde la ralentización indicada.

Thanks for the excellent work. Following the comment in #59, I am trying to train dmoe_760m using 16 GPUs (2 nodes) by changing distributed arguments to set up for two nodes but it is very slow in terms of elapsed time per iteration (ms). Can you suggest an optimal training configuration for multi-node training? A full-fledged multi-training script would be very helpful.

@tgale96

#!/bin/bash
export PYTHONPATH="/dataset/g_ckpt/gaoyuanz/megablocks-public/third_party/Granite-Megatron-LM:${PYTHONPATH}"

export NCCL_SOCKET_IFNAME="ib,bond"
export NCCL_IB_CUDA_SUPPORT=1
export NCCL_IB_PCI_RELAXED_ORDERING=1
export UCX_IB_PCI_RELAXED_ORDERING=on
export CUDA_DEVICE_ORDER=PCI_BUS_ID
export NCCL_SOCKET_NTHREADS=2
export NCCL_NSOCKS_PERTHREAD=4
export CUDA_DEVICE_MAX_CONNECTIONS=1
export TOKENIZERS_PARALLELISM=false

MASTER_ADDR=$(echo ${LSB_MCPU_HOSTS} | tr ' ' '\n' | head -n 1)
MASTER_PORT=5${LSB_JOBID: -5:-1}
NNODES=$(echo ${LSB_MCPU_HOSTS} | tr ' ' '\n' | sed 'n; d' | wc -w)
GPUS_PER_NODE=$(echo $CUDA_VISIBLE_DEVICES | tr ',' '\n' | wc -w)
NODE_RANK=$(($(echo ${LSB_MCPU_HOSTS} | tr ' ' '\n' | sed 'n; d' | grep -n -m1 $HOSTNAME | cut -d':' -f1)-1))

EXPERIMENT_NAME="g-moe-1x4"

EXP_DIR="g-dmoe"

# scaling law: 16B tokens @ 760M = 32k steps.
#
# 512 * 1k * 400k = 200b tokens.
# 512 * 1k * 200k = 100b tokens.
# 512 * 1k * 100k = 50b tokens (default).
# 512 * 1k * 20k = 10b tokens.
TRAINING_STEPS=20000
if [ -n "${2}" ]; then
    TRAINING_STEPS=$2;
fi

##
### Pre-training for GPT2 762M parameter.
##

# MoE hyperparameters.
MOE_ARGUMENTS="\
--moe-num-experts=64 \
--moe-loss-weight=0.1 \
--moe-top-k=1"

# Distributed hyperparameters.
DISTRIBUTED_ARGUMENTS="\
--nproc_per_node $GPUS_PER_NODE \
--nnodes $NNODES \
--node_rank $NODE_RANK \
--master_addr $MASTER_ADDR \
--master_port $MASTER_PORT"

# Model hyperparameters.
MODEL_ARGUMENTS="\
--num-layers 24 \
--hidden-size 1536 \
--num-attention-heads 16 \
--seq-length 1024 \
--max-position-embeddings 1024 \
--activation-function gelu \
--attention-head-type multihead \
--normalization-function layernorm"

# Training hyperparameters.
TRAINING_ARGUMENTS="\
--micro-batch-size 4 \
--global-batch-size 2048 \
--train-iters ${TRAINING_STEPS} \
--lr-decay-iters ${TRAINING_STEPS} \
--lr 0.0004 \
--min-lr 0.00004 \
--lr-decay-style cosine \
--lr-warmup-fraction 0.01 \
--clip-grad 1.0 \
--init-method-std 0.01"

PILE_DATASET="\
1.0 \
/dataset/bluepile/slim_pajama_gptneox_megatron/train/chunk1 \
1.0 \
/dataset/bluepile/slim_pajama_gptneox_megatron/train/chunk2 \
1.0 \
/dataset/bluepile/slim_pajama_gptneox_megatron/train/chunk3 \
1.0 \
/dataset/bluepile/slim_pajama_gptneox_megatron/train/chunk4 \
1.0 \
/dataset/bluepile/slim_pajama_gptneox_megatron/train/chunk5 \
1.0 \
/dataset/bluepile/slim_pajama_gptneox_megatron/train/chunk6 \
1.0 \
/dataset/bluepile/slim_pajama_gptneox_megatron/train/chunk7 \
1.0 \
/dataset/bluepile/slim_pajama_gptneox_megatron/train/chunk8 \
1.0 \
/dataset/bluepile/slim_pajama_gptneox_megatron/train/chunk9 \
1.0 \
/dataset/bluepile/slim_pajama_gptneox_megatron/train/chunk10"

# NOTE: We don't train for enough tokens for the
# split to matter.
DATA_ARGUMENTS="\
--data-path ${PILE_DATASET} \
--tokenizer-type HuggingFaceTokenizer \
--tokenizer-path /dataset/g_ckpt/cobol_exp/Granite-Megatron-LM/tokenizers/gpt-neox-20b \
--make-vocab-size-divisible-by 1024 \
--split 969,30,1"

COMPUTE_ARGUMENTS="\
--fp16 \
--DDP-impl local \
--moe-expert-model-parallelism \
--no-async-tensor-model-parallel-allreduce \
--use-flash-attn"

CHECKPOINT_ARGUMENTS="\
--save-interval 2000 \
--save ./${EXP_DIR}"

EVALUATION_ARGUMENTS="\
--eval-iters 100 \
--log-interval 1 \
--eval-interval 1000"

python -m torch.distributed.launch ${DISTRIBUTED_ARGUMENTS} \
       pretrain_gpt.py \
       ${MOE_ARGUMENTS} \
       ${MODEL_ARGUMENTS} \
       ${TRAINING_ARGUMENTS} \
       ${DATA_ARGUMENTS} \
       ${COMPUTE_ARGUMENTS} \
       ${CHECKPOINT_ARGUMENTS} \
       --fix-infiniband \
       ${EVALUATION_ARGUMENTS} |& tee ./${EXP_DIR}/train-20k.log