I can't understand the difference between SageMaker instance count and Data parallelism. As we already have a feature that can specify how many instances we train model when we write a training script using sagemaker-sdk.
However, in 2021 re:Invent, SageMaker team launched and demonstrated SageMaker managed Data Parallelism and this feature also provides distributed training.
I've searched a lot of sites for letting me know about that, but I can't find really clear demonstration. I share some stuffs explaining the concept I mentioned closely. Link : https://godatadriven.com/blog/distributed-training-a-diy-aws-sagemaker-model/