Searching for Plans You Can Actually Build: A Realizability-Aware Full-Space Optimizer for MoE Training and Serving
On the map: Mixture-of-experts → Efficient MoE training and inference systems
Abstract (arXiv)
Mixture-of-Experts (MoE) systems split a program's plan space in two: the space a cost model can rank, and the smaller space a real toolchain can actually build. Automatic optimizers rank the first and silently assume the two coincide -- so they can return a plan that is optimal on paper and impossible to emit. We present moefs, a realizability-aware full-space optimizer for MoE training and serving that makes deployment realizability a first-class search constraint. moefs closes a three-tier search over parallelism, schedule, and kernels; it emits both a Megatron training stack and an SGLang serving stack from a single plan; and it prices, rather than forbids, the realization overheads it measures. We evaluate across two hardware generations. On 2x RTX4090, the searched training plan edges the strongest hand-tuned baseline by +0.9% (and clears the 0.98x acceptance bar by +2.9%); on 8x H800, the searched serving plan matches the hand-tuned configuration at a 1.0304 throughput ratio. We hold failures to the same standard: on 8x H800 training, the searched plan is a computable, honest FAIL at 0.9338 of the best hand-tuned throughput, losing on a single schedule flag. All predictions are pre-registered in a frozen, artifact-hashed adjudication file before the H800 runs, and every outcome is reported as-is.
Key facts. Cited by 1 paper in the map (data through 14 Oct 2026). Placed in Efficient MoE training and inference systems, one of 12 directions in Mixture-of-experts. Builds on 21 of its 32 references that are in the map. First posted on arXiv 21 Jul 2026.
Builds on
21 of 32 references.
Closest ancestors · 11
Same direction, newest first
- 2026UltraEP: Unleash MoE Training and Inference on Rack-Scale Nodes with Near-Optimal Load Balancing2 Jun
- 2026UniEP: Unified Expert-Parallel MoE MegaKernel for LLM Training21 Apr
- 2025Training Report of TeleChat3-MoE30 Dec
- 2025UCCL-EP: Portable Expert-Parallel Communication22 Dec
- 2025FlashMoE: Fast Distributed MoE in a Single Kernel5 Jun
- 2025MegaScale-MoE: Large-Scale Communication-Efficient Training of Mixture-of-Experts Models in Production16 May
- 2025MoE-CAP: Benchmarking Cost, Accuracy and Performance of Sparse Mixture-of-Experts Systems16 May
- 2025Comet: Fine-grained Computation-communication Overlapping for Mixture-of-Experts27 Feb
- 2024Lancet: Accelerating Mixture-of-Experts Training via Whole Graph Computation-Communication Overlapping30 Apr
- 2022MegaBlocks: Efficient Sparse Training with Mixture-of-Experts29 Nov
- 2022Tutel: Adaptive Mixture-of-Experts at Scale7 Jun
Other references · 10
- 2017Outrageously Large Neural Networks: The Sparsely-Gated Mixture-of-Experts Layercited by 3,509
- 2021Switch Transformers: Scaling to Trillion Parameter Models with Simple and Efficient Sparsitycited by 3,073
- 2019Megatron-LM: Training Multi-Billion Parameter Language Models Using Model Parallelismcited by 1,868
- 2020GShard: Scaling Giant Models with Conditional Computation and Automatic Shardingcited by 1,631
- 2024Vidur: A Large-Scale Simulation Framework For LLM Inferencecited by 117
- 2022Galvatron: Efficient Transformer Training over Multiple GPUs Using Automatic Parallelismcited by 53
- 2023FlexMoE: Scaling Large-scale Sparse Pre-trained Model Training via Dynamic Device Placementcited by 53
- 2025Triton-distributed: Programming Overlapping Kernels on Distributed AI Systems with the Triton Compilercited by 25
- 2025TileLink: Generating Efficient Compute-Communication Overlapping Kernels using Tile-Centric Primitivescited by 24
- 2026DITRON: Distributed Multi-level Tiling Compiler for Parallel Tensor Programscited by 2
Built on by
Citing papers per year: 2026: 1.
1 paper.
- 2026ATTUNE: Agentic Throughput Tuning for LLM Trainingcited by 0
- 2026ATTUNE: Agentic Throughput Tuning for LLM Training13 Oct 2026
Similar, not cited
Close in wording, no citation either way
- 2026HAPMoE: Heterogeneity-Aware Automatic Parallelism Planning for Mixture-of-Experts Models Training
- 2026Holistic Scaling Laws for Optimal Mixture-of-Experts Architecture Optimization
- 2026Moebius: Serving Mixture-of-Expert Models with Seamless Runtime Parallelism Switch
- 2026FastEEP: Fast Intra-Instance Elastic Scaling for Expert-Parallel MoE Serving
- 2026PROBE: Co-Balancing Computation and Communication in MoE Inference via Real-Time Predictive Prefetching
- 2026Where Should Optimizer State Live? Tiered State Allocation for Memory-Efficient Mixture-of-Experts Training
- 2025MoE-Prism: Disentangling Monolithic Experts for Elastic MoE Services via Model-System Co-Designs
- 2026RaMP: Runtime-Aware Megakernel Polymorphism for Mixture-of-Experts