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## 🚀 Feature ## Motivation Currently, [preprocess_ondisk_dataset](https://github.com/dmlc/dgl/blob/4ee0a8bddbd93963b5f078c475381f4ab521d2e1/python/dgl/graphbolt/impl/ondisk_dataset.py#L41) consumes much more memory than the topology of a graph itself during the preprocessing. When loading a graph with 2B nodes and 8B...