reduce_scatter和allreduce的区别在于reduce_scatter近收集梯度均值的一部分,而allreduce将收集所有的梯度。 contiguous_gradients:默认为true 需要调优的参数: allgather_bucket_size:allgather的元素数量,将张量分成较小的桶有助于在通信中更高效的传输数据。这个值越大,每个桶的大小就越大,通信操作可能会变得更快,但...
在上面的更改中,我们将stage字段设置为2,并配置了在ZeRO Stage2 中可用的其他优化选项。例如,我们启用了contiguous_gradients,以减少反向传播期间的内存碎片。这些优化设置的完整描述可在(https://www.deepspeed.ai/docs/config-json/#zero-optimizations-for-fp16-training)找到。有了这些更改,我们现在可以启动训练。
"contiguous_gradients": true, "sub_group_size": 1e9, "reduce_bucket_size": 1e6, "stage3_prefetch_bucket_size": 0.94e6, "stage3_param_persistence_threshold": 1e4, "stage3_max_live_parameters": 1e9, "stage3_max_reuse_distance": 1e9, "stage3_gather_16bit_weights_on_model_save": ...
The Zero Redundancy Optimizer (ZeRO) removes the memory redundancies across data-parallel processes by partitioning the three model states (optimizer states, gradients, and parameters) across data-parallel processes instead of replicating them. By doing this, it boosts memory efficiency compared to class...
{"stage": 2,"allgather_partitions": True,"allgather_bucket_size": 2e8,"overlap_comm": True,"reduce_scatter": True,"reduce_bucket_size": 2e8,"contiguous_gradients": True,"cpu_offload": False}}model_engine, optimizer, _, _ = deepspeed.initialize(args=params,model=model,model_parameters...
{ "zero_optimization": { "stage": 2, "offload_optimizer": { "device": "cpu", } "contiguous_gradients": true, "overlap_comm": true } } 如上所述,除了将stage字段设置为2(启用ZeRO Stage 2,但Stage 1也可以),我们还需要将offload_optimizer设备设置为cpu以启用ZeRO-Offload优化。此外,我们可以...
"contiguous_gradients":true, "sub_group_size":1e9, "reduce_bucket_size":"auto", "stage3_prefetch_bucket_size":"auto", "stage3_param_persistence_threshold":"auto", "stage3_max_live_parameters":1e9, "stage3_max_reuse_distance":1e9, ...
hparams=Hparams(zero_optimization={"stage":3,"offload_optimizer":{"device":"cpu"},"overlap_comm":True,"contiguous_gradients":True,"reduce_scatter":True,"reduce_bucket_size":5e8,"allgather_bucket_size":5e8,"partition_activations":True,"cpu_offload":True,"min_num_size":1e8,"load_from_...
"contiguous_gradients": true, "cpu_offload": true, "cpu_offload_params": false, "cpu_offload_use_pin_memory": false, "sub_group_size": 1e9, "stage3_prefetch_bucket_size": 5e7, "stage3_param_persistence_threshold": 1e6, "stage3_max_live_parameters": 1e9, ...
"loss_scale":0,"initial_scale_power":16,"loss_scale_window":1000,"hysteresis":2,"min_loss_scale":1},"zero_optimization":{"stage":2,"allgather_partitions":true,"allgather_bucket_size":5e8,"reduce_scatter":true,"reduce_bucket_size":5e8,"overlap_comm":false,"contiguous_gradients":true...