Organizations: State Key Laboratory of AI Safety, Institute of Computing Technology, Chinese Academy of Sciences · University of Chinese Academy of Sciences · ETH Zürich · City College of New York, City University of New York, USA · Technical University of Munich · Fuzhou University · Xiamen Institute of Data Intelligence, Xiamen, China
Diffusion-based world models have shown strong potential for unified world simulation, but the iterative denoising remains too costly for interactive use and long-horizon rollouts. While feature caching can accelerate inference without training, we find that policies designed for single-modal diffusion transfer poorly to world models due to two world-model-specific obstacles: token heterogeneity from multi-modal coupling and spatial variation, and non-uniform temporal dynamics where a small set of hard tokens drives error growth, making uniform skipping either unstable or overly conservative. We propose WorldCache, a caching framework tailored to diffusion world models. We introduce Curvature-guided Heterogeneous Token Prediction, which uses a physics-grounded curvature score to estimate token predictability and applies a Hermite-guided damped predictor for chaotic tokens with abrupt direction changes. We also design Chaotic-prioritized Adaptive Skipping, which accumulates a curvature-normalized, dimensionless drift signal and recomputes only when bottleneck tokens begin to drift. Experiments on diffusion world models show that WorldCache delivers up to \textbf{3.7×} end-to-end speedups while maintaining 98% rollout quality, demonstrating the vast advantages and practicality of WorldCache in resource-constrained scenarios. Our code is released in https://github.com/FofGofx/WorldCache.
Figures & tables
Figure 2: Overview of the proposed WorldCache framework. The pipeline alternates between FULL backbone evaluation and CACHE approximation. (Top) In each full computation step, tokens are partitioned into Stable, Linear, and Chaotic groups based on their curvature κ . (Bottom) During caching steps, heterogeneous predictors (Reuse, Linear Extrapolation, or Damped Update) are applied accordingly. (Left) The Chaotic-prioritized Adaptive Skipping (CAS) mechanism accumulates a curvature-normalized drift score Eacc specifically from chaotic tokens, triggering a full computation only when critical drift is detected.
Figure 3: An illustration of token heterogeneity. (a) Modality and Spatial Variance: Distinct patterns between modalities and across spatial regions. (b) Trajectory Dynamics: Three trajectory trends: static, predictable, and sharp, non-linear direction shifts that defy simple extrapolation. More analysis in Appendix Sec. E
Figure 4: Mechanism and effectiveness of the Damped Update. (a) Trajectory Illustration: Damped update stabilizes prediction through historical vt⋆−1 . (b) Quantitative Error Analysis: Damped update reduces chaotic tokens cache error as the prediction window k increases.
Figure 5: An illustration of non-uniform temporal dynamics. We plot the feature difference magnitude across denoising steps for different token percentiles ( p25 to p100 ). The global drift is dominated by a small subset of ”hard” tokens (top percentile, red line), while the majority remain stable. More analysis in Appendix Sec. F .
Method
Benchmark Evaluation
Perceptual Metrics
Acceleration & Memory
WorldScore Static ↑
WorldScore Dynamic ↑
PSNR ↑
SSIM ↑
LPIPS ↓
Latency(s) ↓
Speed ↑
Memory Overhead(GB) ↓
HunyuanVoyager-13B ( Huang et al., 2025 ) ( 512×768p,frames=49 )
Voyager
66.28
46.40
∞
1.000
0.000
1053.7
1.00 ×
50.44
DuCa
53.87
37.71
16.66
0.508
0.486
811.5*
1.30 ×
109.70
ToCa
47.49
33.24
15.51
0.409
0.558
1038.4*
1.01 ×
107.35
TaylorSeer
62.46
43.72
18.32
0.615
0.293
1195.2*
0.88 ×
163.79
Table 1: Quantitative comparison on Image-to-World generation. Bold : the best result. *Note: Layer-wise methods marked with * exceed single-GPU memory limits, requiring CPU offloading which incurs transmission latency.
Table 9: Broader evaluation on longer LingBot rollouts beyond the 49-frame main setting.
Model
WorldCache Overhead (s) ↓
End-to-End Latency (s) ↓
Overhead / Latency ↓
LingBot-14B
0.189
348.7
0.054%
Voyager-13B
0.137
288.6
0.047%
Aether-5B
0.064
107.2
0.060%
Appendix
Table 10: Runtime overhead of WorldCache control logic.
Context Length
Baseline Mem.(GB) ↓
WorldCache Mem.(GB) ↓
Extra Mem.(GB) ↓
Speed ↑
49
49.37
49.39
0.02
2.41 ×
81
55.87
55.89
0.02
2.47 ×
161
71.32
71.35
0.03
2.53 ×
Appendix
Table 11: Memory behavior of WorldCache as context length increases.
Figure 7: More visualization of token heterogeneity. We visualize both RGB tokens and Depth tokens of different prompts across 50 denoising steps in HunyuanVoyager ( Huang et al., 2025 ) . The distinct patterns between RGB and Depth, as well as the spatial variance within each map, underscore the necessity of heterogeneous processing.
Figure 8: Visualization of non-uniform temporal error dynamics. We plot the prediction error accumulation across different token percentiles ( p25 to p100 ). The results show that global variance is dominated by the top percentile of “chaotic” tokens (red line), while the majority of tokens ( p50 and below) remain stable. This supports our strategy of monitoring the Chaotic group rather than the global mean.
Figure 9: Visualization of temporal scale variance. Histograms show the distribution of feature values at different denoising steps. The numerical range fluctuates by orders of magnitude (e.g., thousands at Step 1 vs. single digits at Step 37), proving that fixed thresholds on raw values are unreliable and validating the necessity of our dimensionless drift indicator.
Figure 10: More visual comparison between WorldCache and existing methods.
Figure 11: More visual comparison between WorldCache and existing methods.
Figure 12: More visual comparison between WorldCache and existing methods.
Figure 13: More visual comparison between WorldCache and existing methods.