Semi-supervised learning aims to infer class labels using only a small fraction of labeled data. In graph-based semi-supervised learning, this is typically achieved through label propagation to predict labels of unlabeled nodes. However, in real-world applications, data often arrive incrementally in batches. Each time a new batch appears, reapplying the traditional label propagation algorithm to recompute all labels is redundant, computationally intensive, and inefficient. To address the absence of an efficient label propagation update method, we propose DynLP, a novel GPU-centric Dynamic Batched Parallel Label Propagation algorithm that performs only the necessary updates, propagating changes to the relevant subgraph without requiring full recalculation. By exploiting GPU architectural optimizations, our algorithm achieves on average 13x and upto 102x speedup on large-scale datasets compared to state-of-the-art approaches.
Figures & tables
Figure 1. Evolution of the label-propagation algorithm over six iterations.
Figure 2. CUDA Kernel design for sparsification and connected component finding
Figure 3. Block level granularity to process nodes in the frontier list
Figure 4. Memory latency hiding
Method
Incremental
Decremental
Parallelism
Update
Target graph
Memory Optim.
ItLP ( Zhu et al., 2003a )
✓
✗
✗
✗
Dense
Compression
CAGNN ( Zhu et al., 2020 )
✓
✗
✓
✗
Dense
Compression
A2LP ( Zhang et al., 2020 )
✓
✗
✓
✗
Sparse
KNN
StLP ( Wagner et al., 2018 )
✓
✓
✓
✗
Dense
N/A
Approx StLP ( Ponte et al., 2024 )
✓
✓
✓
✗
Dense
Sparse Inverse
DynLP [this work]
✓
✓
✓
✓
Sparse
CSR
Table 1. Baseline methods compared with DynLP .
Dataset
∣V∣
∣E∣
IMDB Review ( Maas et al., 2011 )
50,000
125K
ImageNet ( Deng et al., 2009 )
50,000
125K
Yelp Review ( mhamine, n.d. )
6,990,280
17M
Amazon Household Review ( Hou et al., 2024 )
25,600,000
64M
Amazon Book Review ( Hou et al., 2024 )
29,500,000
73M
Random Dataset
50,000,000
{75M,62M,175M}
Table 2. Dataset description
Figure 5. Iterations and execution time of DynLP across datasets.
Figure 6. Impact of δ on DynLP
Figure 7. Iteration and speedup comparison between DynLP and ItLP as vertex count varies.
Figure 8. Speedup comparison between DynLP and StLP
Figure 9. Performance comparison with machine learning methods
Dataset
ItLP
StLP
DynLP
CAGNN
IMDB
652.25
3,196.41
439.21
8,545.53
Yelp
18,283.94
23,182.12 ( γ=10 )
3,712.82
40,853.31
Household
678,939.29
-
18,232.38
-
Book
783,925.09
-
19,927.31
-
Table 3. Execution time comparison across datasets.
Method
50K
500K
5M
T(ms)
A
T(ms)
A
T(ms)
A
ItLP
1,120
100
4,738
100
11,929
100
StLP
1,637
100
–
–
–
–
StLP ( γ=0.1 )
5,637
72.9
–
–
–
–
StLP ( γ=1.0 )
3,989
83.5
–
–
–
–
StLP ( γ=10.0 )
1,563
56.3
5,989
54.2
21,637
49.5
Table 4. Performance comparison on random graph with varied batch sizes (T: Execution time, A: Accuracy)