TurboDiffusion Integration Notes
July 16, 2026 ยท View on GitHub
TurboT2AV adapts TurboDiffusion's inference stack to the LTX-2 joint audio-video transformer. The integration is intentionally limited to inference; the TurboT2AV distillation and training pipeline remains independent.
Reused Components
- SageSLA: TurboDiffusion's sparse-linear attention design and SLA compensation path are wrapped for LTX-2 video and audio self-attention.
- FastNorm: module and functional RMSNorm/LayerNorm operations are replaced with fused implementations, together with LTX-specific modulation, residual, and rotary-embedding helpers.
- W8A8 Linear: selected weights are quantized to INT8 at model initialization, and activations are dynamically quantized before transformer Linear operations. A BF16 copy is also retained because unsupported shapes use native Linear, so this path targets compute speed rather than checkpoint compression.
The recommended path combines SageSLA topk=0.3, FastNorm, and TileLang W8A8.
The one-command installer pins the tested SageAttention and SpargeAttn commits
and applies build-only compatibility patches. They keep architecture-specific
CUDA sources scoped to their valid targets and do not change attention kernels.
It also pins the tested TileLang and TVM FFI versions so a fresh environment
does not resolve an incompatible TVM FFI runtime.
Differences From TurboDiffusion
| Area | TurboDiffusion | TurboT2AV integration |
|---|---|---|
| Model | Wan text-to-video transformer | LTX-2 joint audio-video transformer |
| Tested GPU | RTX 5090 in the published latency figure | NVIDIA H20 |
| Memory | Includes a CPU-offload stage | Full model remains on the H20; no CPU offload |
| Attention | Wan self-attention layout | LTX video/audio self-attention adapters; masked text cross-attention remains native |
| W8A8 kernel | Original CUTE/SM80 blockwise kernel | TileLang post-scale kernel tuned for H20 and LTX FFN shapes |
| Distillation | rCM is a separate acceleration stage | Uses the existing four-step TurboT2AV student checkpoint |
The TileLang kernel keeps INT8 accumulation continuous across the K dimension and applies activation/weight scales in the epilogue. This adaptation is used because TurboDiffusion's original W8A8 kernel did not outperform BF16 Linear on the tested H20 LTX shapes.
End-to-End Result
The following generator-only measurements use one H20, 121 frames, and a
1024x1792 output resolution. Stages are cumulative.
| Stage | Latency | Speedup vs previous | Speedup vs teacher |
|---|---|---|---|
| LTX-2-19B teacher, 40 steps | 318.7405s | - | 1.00x |
| + TileLang W8A8 and FastNorm | 233.3424s | 1.37x | 1.37x |
| + four-step TurboT2AV student | 12.1655s | 19.18x | 26.20x |
+ SageSLA topk=0.3 and text trimming | 5.8505s | 2.08x | 54.48x |
The fully accelerated four-step student is 2.82x faster than the pure four-step
student (16.5245s/video) and 54.48x faster than the 40-step teacher
(318.7405s/video).
topk=0.3 was selected as the practical speed/quality setting from paired
visual comparisons; sparse attention is not numerically lossless and should be
revalidated for a different resolution or prompt distribution.