| --- |
| base_model: Qwen/Qwen3.5-4B |
| library_name: transformers |
| tags: |
| - vision-language-navigation |
| - r2r |
| - simplememvln |
| --- |
| # SimpleMemVLN R2R fullcontext — option B |
|
|
| **Not yet evaluated in Habitat.** Training loss is not a navigation success metric. |
| The observation-before-action alignment is declared but not independently verified |
| from collector source or Habitat replay. |
|
|
| ## Recipe |
| Independently initialized from Qwen/Qwen3.5-4B revision |
| `851bf6e806efd8d0a36b00ddf55e13ccb7b8cd0a`, not from the other variant. |
| Code commit: `d50174daf1fda692849cfaa3e69286a504339fb2`. |
| Serializer: `vln_append_only_chat_v1`. Native LLM text-action head (option B), |
| gold action history, per-action mean token CE including assistant terminator. |
| Frozen vision/merger; trainable text backbone and LLM head. BF16, ZeRO-2, |
| nonreentrant full-episode gradient checkpointing, no truncation or TBPTT. |
| Four H100 GPUs, one episode/rank, GAS 2: global batch 8 episodes. |
| R2R train: 10,819 unique episodes, 631,244 actions; distributed repetition |
| adds one episode per epoch. Three epochs, 4,059 updates, 122 warmup updates. |
| Peak LR 5e-6, cosine decay to 10% of peak, weight decay 0.01, seed 429. |
| Memory mode: `fullcontext`. Window8 keeps prefix plus eight complete steps |
| for full-attention KV; persistent GDN state and gradients are not reset. |
|
|
| ## Snapshots |
| `epoch-1`, `epoch-2`, `epoch-3` correspond to updates 1353, 2706, 4059. |
| **Epochs 1–2 are mid-schedule snapshots of one 3-epoch cosine run**, not |
| independently trained one-/two-epoch models. All optimizer states remain local. |
|
|
| ## Loading and integrity |
| These weights use the SimpleMemVLN navigation wrapper, not an unmodified |
| `AutoModel` state dictionary. Download an epoch directory and load it with |
| `qwen_vl.train.vln_runtime.load_checkpoint(path, model_path)` using the pinned |
| base snapshot and the recorded environment. Navigation metadata contains the |
| complete serializer and memory contract. |
| `SHA256SUMS.json` records model/configuration/metric hashes. The uploader |
| downloads every uploaded file at the immutable commit revision and verifies |
| SHA256 before marking publication complete locally. Dataset images, credentials |
| and optimizer states are not published. |
|
|
