Files
Xuan-Son Nguyen 097cf33d94 model: support vllm decision 2 model (#30378)
* models: support pplx-decider

* vllm d2

* update

* clarify naming rule

* stricter validation

* fix ci

* rm redundant filter_tensors
2026-10-12 13:39:55 +02:00

108 lines
4.9 KiB
Python

from __future__ import annotations
import json
from pathlib import Path
from typing import Any, Callable, Iterator, TYPE_CHECKING
if TYPE_CHECKING:
from torch import Tensor
from .base import ModelBase, gguf, logger
from .qwen import Qwen3Model
def _is_vllm_decision2_checkpoint(dir_model: Path) -> bool:
if not (dir_model / "config.json").is_file():
return False
with open(dir_model / "config.json", encoding="utf-8") as f:
return json.load(f).get("decision_format") == "vllm-sr-decision"
@ModelBase.register_hparams_loader(_is_vllm_decision2_checkpoint)
def _load_vllm_decision2_hparams(dir_model: Path) -> dict[str, Any]:
logger.info("gguf: detected vllm-sr Decision 2.0 checkpoint")
with open(dir_model / "config.json", encoding="utf-8") as f:
package = json.load(f)
hparams = ModelBase.load_hparams((dir_model / package["backbone"]["config"]).parent, False, guess=False)
hparams["architectures"] = ["VllmDecision2Model"]
with open(dir_model / package["model_config"], encoding="utf-8") as f:
hparams["decision"] = json.load(f)
with open(dir_model / "score_bias.json", encoding="utf-8") as f:
hparams["decision"]["score_bias"] = json.load(f)["offsets"]
return hparams
@ModelBase.register("VllmDecision2Model")
@ModelBase.example("vllm-sr/Decision-2.0-Kai-0.6B")
class VllmDecision2Model(Qwen3Model):
model_arch = gguf.MODEL_ARCH.VLLM_DECISION2
# torch.nn.LayerNorm default, used by the head
_HEAD_NORM_EPS = 1e-5
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
head = self.hparams["decision"]
if head["architecture"] != "qwen3-text-endpoints-global-query-shared-bilinear-mlp" or head["head_variant"] != "shared":
raise ValueError(f"unsupported decision head: {head['architecture']}")
def index_tensors(self, *args, **kwargs) -> dict[str, Callable[[], Tensor]]:
# the backbone weights are in their own directory
dir_model, self.dir_model = self.dir_model, self.dir_model / "backbone"
try:
return super().index_tensors(*args, **kwargs)
finally:
self.dir_model = dir_model
def get_tensors(self) -> Iterator[tuple[str, Tensor]]:
yield from super().get_tensors()
from safetensors.torch import load_file
for name, data in load_file(self.dir_model / "decision_head.safetensors").items():
yield "decision_head." + name, data
def tensor_force_quant(self, name: str, new_name: str, bid: int | None, n_dims: int) -> gguf.GGMLQuantizationType | bool:
# the head is computed in F32
if new_name.startswith("decision."):
return gguf.GGMLQuantizationType.F32
return super().tensor_force_quant(name, new_name, bid, n_dims)
def set_vocab(self):
super().set_vocab()
self.gguf_writer.add_chat_template([{"name": "systemone", "template": self._systemone_template()}])
@classmethod
def _systemone_template(cls) -> str:
# prompt follows decision2/_vendor/dev2model/decision_model.py (segments) of the model repo
# the pieces of the prompt are tokenized one by one, the server gives the text that separates them (sep)
# and the text that starts the span of a question or of an option (mark_question, mark_option)
# the head reads the last token of each option and the last token of the question
# the start of an option is a piece of its own, so that the spans of two options are not joined
# the keys of JSON objects are given in sorted order
def text(value: str) -> str:
return "{{ " + json.dumps(value) + " }}"
def render(name: str) -> str:
return "{{ " + name + " if " + name + " is string else " + name + " | tojson(separators=[',', ':']) }}"
option = (
"{% set d = o.description %}"
"{% if q.type == 'noul' and d is none %}{% set d = 'Yes' if o.key == 'true' else 'No' %}{% endif %}"
"{{ {'description': d, 'key': o.key} | tojson(separators=[',', ':']) }}"
)
return (
"{% for q in questions %}"
+ text("Context:\n") + render("state")
+ text("\n\nTask type: ") + "{{ q.type }}" + text("\nQuestion:\n") + render("q.instructions") + text("\nOptions:")
+ "{% for o in q.options %}{{ sep }}" + text("\n<option>\n") + "{{ sep }}{{ mark_option }}" + option + text("\n</option>") + "{% endfor %}"
+ "{{ sep }}{{ mark_question }}" + text("\n\nSelect the single option best supported by the context and instructions.\nDecision:")
+ "{% endfor %}"
)
def set_gguf_parameters(self):
super().set_gguf_parameters()
self.gguf_writer.add_decision_type(gguf.DecisionType.VLLM_DECISION2)
self.gguf_writer.add_layer_norm_eps(self._HEAD_NORM_EPS)
for offsets in self.hparams["decision"]["score_bias"].values():
self.gguf_writer.add_decision_score_bias(offsets)