GNNAutoscale¶
Fey, M., Lenssen, J. E., Weichert, F., & Leskovec, J. (2021). GNNAutoScale: Scalable and Expressive Graph Neural Networks via Historical Embeddings. Proceedings of the 38th International Conference on Machine Learning, 3294–3304. https://proceedings.mlr.press/v139/fey21a.html
AI papers are sooo much easier to read than those OSDI's papers.
Historical Embeddings¶
Let \(\bm h_v^{(l)}\) denote the node embedding in layer \(l\) of a node \(v \in B\) in a mini-batch \(B \subseteq V\). For the general message scheme, the execution of \(\bm f_{\bm \theta}^{(l+1)}\) can be formulated as:
For out-of-mini-batch nodes, approximate their embeddings via historical embeddings acquired in previous iterations of training
Cite "Chen, J., Zhu, J., and Song, L. Stochastic training of graph convolutional networks with variance reduction. In ICML, 2018b." here
Additional advantages¶
-
GAS trains over all the data: In GAS, a GNN will make use of all available graph information, i.e. no edges are dropped, which results in lower variance and more accurate estimations.
-
GAS enables constant inference time complexity: The time complexity of model inference is reduced to a constant factor, since we can directly use the historical embeddings of the last layer to derive predictions for test nodes.
-
GAS is simple to implement: Our scheme does not need to maintain recursive layer-wise computation graphs, which makes its overall implementation straightforward and comparable to full-batch training.
-
GAS provides theoretical guarantees
Theoretical analysis¶
...
Implementation (Pipeline)¶
Our approach accesses histories to account for any data outside the current mini-batch, which requires frequent data transfers to and from the GPU.
- pulling historical embeddings for each layer asynchronously at the beginning of each optimization step > Synchronization is done by synchronizing the respective CUDA stream before inputting the transferred data into the GNN layer.
- The same strategy is applied for pushing information to the history.