Graph Neural Networks (GNNs) are widely used for learning on graph-structured data, but scaling GNN training to massive graphs remains challenging. To enable scalable distributed training, graphs are divided into smaller partitions that are distributed across multiple machines such that inter-machine communication is minimized and computational load is balanced. In practice, existing partitioning approaches face a fundamental trade-off between partitioning overhead and partitioning quality. We propose EmbedPart, an embedding-driven partitioning approach that achieves both speed and quality. Instead of operating directly on irregular graph structures, EmbedPart leverages node embeddings produced during the actual GNN training workload and clusters these dense embeddings to derive a partitioning. EmbedPart achieves more than 100x speedup over Metis while maintaining competitive partitioning quality and accelerating distributed GNN training. Moreover, EmbedPart naturally supports graph updates and fast repartitioning, and can be applied to graph reordering to improve data locality and accelerate single-machine GNN training. By shifting partitioning from irregular graph structures to dense embeddings, EmbedPart enables scalable and high-quality graph data optimization.
Figures & tables
Figure 1. (a) Traditional approaches perform graph partitioning or reordering as a preprocessing step based solely on the graph structure. (b) Our approach ( EmbedPart ) derives partitions from node embeddings produced during GNN training. These embeddings capture both structural and feature information and enable partitioning or reordering directly in the dense embedding space using scalable clustering.
Figure 2. Vertices are assigned to partitions. Edges connecting vertices of different partitions are cut.
Figure 3. Distributed GNN training pipeline: 1 the input graph is partitioned into k partitions; 2 hyperparameters for the GNN are selected; 3 the model is trained in a distributed fashion; 4 the model is evaluated; repeat 3 - 4 with the next hyperparameter set; 5 once the final model is trained, it is applied to downstream tasks.
Figure 4. EmbedPart overview: The input to EmbedPart is like in GNN training, a graph with features that are attached to nodes. In Phase 1, we train a GNN model (the actual workload) and get node embeddings. At any point, the process can transition to Phase 2, where clustering on the embeddings assigns nodes to clusters. To maintain balanced distributed training, nodes are migrated from overloaded to underloaded clusters such as node 4. The resulting clusters are then used for graph partitioning. Finally, the process returns to Phase 1 to continue GNN training with the improved data layout.
Graph
Vertices
Edges
Mean Deg.
arxiv
169,343
1,166,243
13.77
reddit
232,965
114,615,892
983.98
products
2,449,029
123,718,280
101.03
papers100M
111,059,956
1,615,685,872
29.10
Table 1. Evaluation graphs along with the number of vertices, number of edges, and mean degree.
Table 2. Average edge-cut ratio (lower is better) after different numbers of GNN training epochs.
Figure 5. Loss and accuracy for reddit over epochs.
Table 3. Edge-cut ratio reduction by an untrained GNN compared to random partitioning in percentage. Larger is better.
Figure 6. Comparison of partitioning time speedups and edge-cut reductions.
Figure 7. Partitioning run-time on different graphs and number of partitions. Lower is better
Figure 8. Partitioning quality metrics: Edge-cut ratio on different graphs and number of partitions. Lower is better.
Figure 9. Speedup of partitioners over random partitioning. Larger is better.
Figure 10. Achieved speedups for distributed GNN training on different graphs, number of GPUs, and number of GNN layers.
Graph / size (%)
arxiv
papers100M
products
reddit
G1 / 10
0.56
0.50
0.30
0.32
G2 / 30
0.48
0.50
0.23
0.28
G3 / 50
0.46
0.49
0.21
0.27
G4 / 70
0.46
0.49
0.20
0.27
G5 / 90
0.45
0.49
0.20
0.26
G / 100
0.45
0.49
0.21
0.26
Table 4. Average edge-cut ratio (lower is better) when training on different graph snapshots of G . The trained model is applied to the latest graph G without retraining.
CPU
GPU
Strategy
arxiv
products
reddit
papers100M
arxiv
products
reddit
papers100M
Cuttana
1.029
1.149
1.110
0.951
1.001
2.052
1.026
OOM
Ldg
1.037
1.127
1.145
1.022
1.002
2.021
1.007
OOM
Metis
0.989
1.161
1.175
0.935
1.002
2.077
1.011
OOM
Spinner
1.003
1.127
1.136
0.955
1.000
2.018
1.011
OOM
EmbedPart-l-3
1.025
1.147
1.147
0.954
1.001
1.995
1.013
OOM
Table 5. Speedups through reordering for single-machine GNN training. Larger is better. OOM indicates out-of-memory errors.
Average graph bandwidth
Edge-cut ratio
Strategy
arxiv
products
reddit
papers100M
arxiv
products
reddit
papers100M
EmbedPart-l-3
74K
1022K
154K
57594K
0.471
0.233
0.477
0.564
EmbedPart-l-3 -unbalanced
56K
659K
124K
38407K
0.360
0.162
0.372
0.286
EmbedPart-v-3
79K
1196K
151K
61468K
0.680
0.357
0.401
0.716
EmbedPart-v-3 -unbalanced
72K
875K
123K
44247K
0.619
0.269
0.293
0.271
EmbedPart-l-2
71K
1025K
154K
55970K
0.470
0.233
0.459
0.504
Table 6. Both the average graph bandwidth and edge-cut ratio are better (lower) for the unbalanced EmbedPart .
Full-graph GNN training delivers high accuracy but scales poorly on multi-server clusters due to heavy, irregular inter-node embedding exchanges. We present SNI-GNN, a SmartNIC-assisted full-graph training system that reduces communication while preserving accuracy by predicting remote embeddings in-network. SNI-GNN deploys a lightweight linear-trend predictor on SmartNICs to refine cached historical embeddings, coupled with an importance-based boundary-node sampling policy and an asynchronous DPU--GPU data pipeline with intermediate-result reuse. We provide error and convergence bounds showing that predictor bias remains controlled under bounded second-order dynamics and yields standard non-convex convergence with inexact gradients. Implemented on NVIDIA BlueField-3, SNI-GNN integrates with state-of-the-art full-graph systems, cuts communication by 21--45%, achieves 1.3--3.6× end-to-end speedups over BNS-GCN and up to 1.29× over baseline SANCUS, with accuracy loss ≤0.01, and scales efficiently to 16 GPUs on graphs with up to tens of millions of edges. These results indicate SmartNIC-based in-network prediction is a practical complement to partitioning and compression techniques for communication-efficient full-graph GNN training at scale.
Guofan Yu, Sitian Chen, Zhenheng Tang +2
Hong Kong Baptist University · Hong Kong University of Science and Technology · Hong Kong University of Science and Technology (Guangzhou)
Graph neural networks (GNNs) are widely used for learning on graph datasets derived from various real-world scenarios. Learning from extremely large graphs requires distributed training, and mini-batching with sampling is a popular approach for parallelizing GNN training. Existing distributed mini-batch approaches have significant performance bottlenecks due to expensive sampling methods and limited scaling when using data parallelism. In this work, we present ScaleGNN, a 4D parallel framework for scalable mini-batch GNN training that combines communication-free distributed sampling, 3D parallel matrix multiplication (PMM), and data parallelism. ScaleGNN introduces a uniform vertex sampling algorithm, enabling each process (GPU device) to construct its local mini-batch, i.e., subgraph partitions without any inter-process communication. 3D PMM enables scaling mini-batch training to much larger GPU counts than vanilla data parallelism with significantly lower communication overheads. We also present additional optimizations to overlap sampling with training, reduce communication overhead by sending data in lower precision, kernel fusion, and communication-computation overlap. We evaluate ScaleGNN on five graph datasets and demonstrate strong scaling up to 2048 GPUs on Perlmutter, 2048 GCDs on Frontier, and 1024 GPUs on Tuolumne. On Perlmutter, ScaleGNN achieves 3.5x end-to-end training speedup over the SOTA baseline on ogbn-products.
Cunyang Wei, Siddharth Singh, Aishwarya Sarkar +7
University of Maryland, College Park, USA · NVIDIA, Inc. · Iowa State University, USA +3
Graph embedding maps graph nodes into low-dimensional vectors to support applications such as recommendation, fraud detection, and graph-based retrieval-augmented generation (GraphRAG). As graphs scale to billions of edges, scalable and efficient graph embedding has become increasingly important. Existing frameworks commonly adopt a sampling-training paradigm, in which mini-batches are constructed by sampling nodes and their neighbors. However, sampling is typically decoupled from evolving embedding quality, causing redundant exploration of well-trained regions while under-sampling undertrained nodes. At the system level, such decoupling further leads to excessive communication, serialized execution, and low resource utilization in distributed environments. We present FeLoG, a feedback loop-driven system for scalable distributed graph embedding. (1) FeLoG introduces feedback-coupled sampling and training, dynamically prioritizing undertrained nodes according to real-time embedding-quality feedback, thereby reducing redundant computation and accelerating convergence. (2) It employs activity-aware communication that compresses frequently occurring node sequences to reduce intra-machine PCIe traffic and selectively synchronizes frequently updated embeddings to reduce inter-machine communication. (3) It adopts a round-interleaved pipeline that overlaps next-round sampling with current-round training to improve CPU-GPU utilization. Experiments against six state-of-the-art baselines on large-scale graphs show that FeLoG achieves an average speedup of 27.9x, reduces communication cost by more than 53.1%, and sustains over 80% CPU-GPU utilization.
Peng Fang, Arijit Khan, Ziqiang Wu +4
Huazhong University of Science and Technology · Bowling Green State University