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neuron-tai/packages/node/meshnet_node/boundary_adapter.py
2026-07-15 23:42:58 +03:00

485 lines
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Python

"""Architecture-defined boundary input/output for distributed Shards (DGR-006).
A public-network Shard is a contiguous range of transformer layers (RALPH runtime
decision #1). For disjoint processes to reproduce whole-model execution, every
Shard must agree on *exactly* what boundary state it consumes and emits:
* The **head** owns token embedding: it accepts token IDs and turns them into the
residual stream. No other Shard may embed tokens.
* **Middle and tail** Shards bypass token embedding entirely; they accept the named
boundary bundle (the residual stream handed over by the previous range).
* A **non-tail** Shard emits the *unnormalized* architecture-defined residual /
boundary — before the final norm, before the LM head, and before any tail-only
row pruning — so the next range sees precisely the state the whole model would
have at that layer index.
* The **tail** owns the final norm + LM head and turns the residual into logits or
a sampled token through an explicit sampling contract.
This module is deliberately backend-agnostic. It enforces the boundary *contract*
and defers the arithmetic to a ``ShardComputation`` (a duck-typed object exposing
``embed_tokens`` / ``run_layers`` / ``final_norm`` / ``lm_head``). The pinned
llama.cpp worker (DGR-008) and the reference PyTorch backend both satisfy that
protocol, and the numpy reference model in the tests proves whole-model versus
two-range parity without any download, GPU, or API credit.
The adapter **fails closed** for uncertified architectures: only architectures
that have passed real certification (dense Llama-family first, per RALPH runtime
decision #13) are accepted. Everything else raises rather than silently guessing a
tensor layout — Qwen3/Qwen3-MoE stays registered-but-dark until DGR-015 certifies
its own adapter.
"""
from __future__ import annotations
from dataclasses import dataclass, field
from enum import Enum
from typing import Any
import numpy as np
# The boundary bundle wire schema version. This is the ``boundary_schema_version``
# carried by ``runtime_recipe.RuntimeRecipeIdentity``; a receiver refuses a bundle
# whose schema it does not implement (forward/backward compatibility is a routing
# concern, not a silent reinterpretation).
BOUNDARY_SCHEMA_VERSION = 1
class BoundaryAdapterError(RuntimeError):
"""Base class for boundary-contract violations."""
class UncertifiedArchitectureError(BoundaryAdapterError):
"""Raised when a boundary adapter is requested for an uncertified architecture.
Failing closed here is a safety property: an unknown architecture has an
unknown tensor layout, so guessing where the residual boundary lives would
silently corrupt distributed output. The architecture must pass real
certification first.
"""
class BoundaryContractError(BoundaryAdapterError):
"""Raised when a Shard is fed the wrong boundary input for its role.
Examples: a head handed a residual bundle instead of token IDs, a middle
Shard handed token IDs it must not embed, or a boundary bundle whose
architecture / schema / seam layer does not match the receiving range.
"""
@dataclass(frozen=True)
class ArchitectureBoundary:
"""The architecture-defined boundary description for one certified adapter.
These fields are what makes the boundary *architecture-defined* rather than a
hardcoded assumption: the residual tensor name, whether the tail normalizes
before the LM head, and whether row pruning is a tail-only concern all come
from here.
"""
adapter: str
boundary_tensor_name: str
boundary_schema_version: int
normalizes_before_head: bool
prunes_rows_at_tail: bool
# Certified architectures only. Dense Llama-family is first (RALPH runtime decision
# #13 + native discipline). Aliases map the many spellings a runtime recipe /
# GGUF / HF config may use onto the single canonical adapter id. Anything not in
# this table fails closed.
_DENSE_LLAMA = ArchitectureBoundary(
adapter="dense-llama",
boundary_tensor_name="residual_stream",
boundary_schema_version=BOUNDARY_SCHEMA_VERSION,
normalizes_before_head=True,
prunes_rows_at_tail=True,
)
_CERTIFIED_ARCHITECTURES: dict[str, ArchitectureBoundary] = {
"dense-llama": _DENSE_LLAMA,
"dense_llama": _DENSE_LLAMA,
"llama": _DENSE_LLAMA,
"llamaforcausallm": _DENSE_LLAMA,
"llamamodel": _DENSE_LLAMA,
}
def certified_architecture(name: Any) -> ArchitectureBoundary:
"""Return the certified boundary description for ``name`` or fail closed.
``name`` may be the canonical adapter id (``dense-llama``), an HF architecture
class (``LlamaForCausalLM``), or a GGUF/config ``model_type`` (``llama``).
Uncertified architectures raise ``UncertifiedArchitectureError``.
"""
if not isinstance(name, str) or not name.strip():
raise UncertifiedArchitectureError(
"architecture adapter must be a non-empty string; "
"the boundary adapter refuses to guess a tensor layout"
)
key = name.strip().lower()
boundary = _CERTIFIED_ARCHITECTURES.get(key)
if boundary is None:
raise UncertifiedArchitectureError(
f"architecture {name!r} is not certified for the boundary adapter; "
f"certified adapters: {sorted(set(v.adapter for v in _CERTIFIED_ARCHITECTURES.values()))}. "
"Uncertified architectures stay registered-but-dark until real "
"certification passes."
)
return boundary
def is_certified_architecture(name: Any) -> bool:
"""Return True when ``name`` maps to a certified boundary adapter."""
try:
certified_architecture(name)
except UncertifiedArchitectureError:
return False
return True
class ShardRole(str, Enum):
"""Where a contiguous layer range sits in the whole model."""
HEAD = "head"
MIDDLE = "middle"
TAIL = "tail"
FULL = "full"
@property
def owns_embedding(self) -> bool:
return self in (ShardRole.HEAD, ShardRole.FULL)
@property
def owns_final_head(self) -> bool:
return self in (ShardRole.TAIL, ShardRole.FULL)
def role_for_range(start_layer: int, end_layer: int, total_layers: int) -> ShardRole:
"""Classify a contiguous inclusive layer range within a model of ``total_layers``."""
if total_layers <= 0:
raise ValueError("total_layers must be positive")
if start_layer < 0 or end_layer < start_layer:
raise ValueError("require 0 <= start_layer <= end_layer")
if end_layer > total_layers - 1:
raise ValueError(
f"end_layer {end_layer} exceeds last layer index {total_layers - 1}"
)
is_head = start_layer == 0
is_tail = end_layer >= total_layers - 1
if is_head and is_tail:
return ShardRole.FULL
if is_head:
return ShardRole.HEAD
if is_tail:
return ShardRole.TAIL
return ShardRole.MIDDLE
@dataclass(frozen=True)
class BoundaryBundle:
"""The versioned named-tensor bundle handed between adjacent Shard ranges.
``residual`` is the *unnormalized* architecture-defined residual stream with
every position row intact (no tail-only pruning). ``next_layer`` is the layer
index the receiving range must start at — it is the overlap-safe effective
start of the seam, so a receiver can reject a bundle meant for a different cut.
"""
architecture_adapter: str
schema_version: int
tensor_name: str
residual: np.ndarray
positions: np.ndarray
next_layer: int
normalized: bool = False
def named_tensor_fields(self) -> dict[str, Any]:
"""Return the wire-shaped description of the residual tensor.
These are exactly the fields the DGR-002 ``NamedTensor`` carries (name,
shape, dtype, byte order, raw bytes), so a worker can serialize this
bundle into the gRPC protobuf without re-deriving them.
"""
residual = np.ascontiguousarray(self.residual)
return {
"name": self.tensor_name,
"shape": list(residual.shape),
"dtype": residual.dtype.name,
"byte_order": _byte_order(residual.dtype),
"data": residual.tobytes(),
}
def pack(self) -> dict[str, Any]:
"""Serialize the bundle to a transport-agnostic dict (proves the seam).
The residual and positions are carried as raw little/big-endian bytes plus
shape/dtype so that a truly disjoint process can reconstruct the exact
array — this is what lets two OS processes reproduce whole-model math.
"""
residual = np.ascontiguousarray(self.residual)
positions = np.ascontiguousarray(self.positions)
return {
"architecture_adapter": self.architecture_adapter,
"schema_version": self.schema_version,
"tensor_name": self.tensor_name,
"next_layer": self.next_layer,
"normalized": self.normalized,
"residual": {
"shape": list(residual.shape),
"dtype": residual.dtype.str,
"data": residual.tobytes(),
},
"positions": {
"shape": list(positions.shape),
"dtype": positions.dtype.str,
"data": positions.tobytes(),
},
}
@classmethod
def unpack(cls, payload: dict[str, Any]) -> "BoundaryBundle":
"""Reconstruct a bundle produced by :meth:`pack`."""
residual = _array_from_wire(payload["residual"])
positions = _array_from_wire(payload["positions"])
return cls(
architecture_adapter=payload["architecture_adapter"],
schema_version=int(payload["schema_version"]),
tensor_name=payload["tensor_name"],
residual=residual,
positions=positions,
next_layer=int(payload["next_layer"]),
normalized=bool(payload.get("normalized", False)),
)
@dataclass(frozen=True)
class SamplingContract:
"""Explicit contract for turning tail logits into a token.
The tail never hides the sampling decision inside the adapter: the contract is
a first-class value so the head/route can reproduce it and so greedy decoding
is deterministic by construction. Only greedy is certified here; temperature /
top-p are declared but must be requested explicitly and are out of scope for
the deterministic parity gate.
"""
mode: str = "greedy"
temperature: float = 1.0
top_p: float = 1.0
def __post_init__(self) -> None:
if self.mode not in ("greedy",):
raise BoundaryContractError(
f"sampling mode {self.mode!r} is not certified; only 'greedy' is "
"deterministic and supported by the boundary adapter today"
)
@classmethod
def greedy(cls) -> "SamplingContract":
return cls(mode="greedy")
def sample(self, last_logits: np.ndarray) -> int:
"""Return the next token id from the final-position logits row."""
logits = np.asarray(last_logits)
if logits.ndim == 2:
# (batch, vocab) — parity harness uses batch size 1.
logits = logits[0]
if logits.ndim != 1:
raise BoundaryContractError(
"sampling expects the pruned final-position logits row"
)
return int(np.argmax(logits))
@dataclass(frozen=True)
class TailOutput:
"""What a tail Shard emits: the sampled token plus the pruned logits row."""
token_id: int
logits: np.ndarray
sampling: SamplingContract
@dataclass
class BoundaryAdapter:
"""Enforces the architecture-defined boundary contract for one Shard range.
Construction fails closed for uncertified architectures. The adapter derives
the Shard's role from its range and drives a duck-typed ``ShardComputation``.
"""
computation: Any
sampling: SamplingContract = field(default_factory=SamplingContract.greedy)
architecture: ArchitectureBoundary = field(init=False)
role: ShardRole = field(init=False)
start_layer: int = field(init=False)
end_layer: int = field(init=False)
total_layers: int = field(init=False)
def __post_init__(self) -> None:
arch_name = getattr(self.computation, "architecture_adapter", None)
self.architecture = certified_architecture(arch_name)
self.start_layer = int(getattr(self.computation, "start_layer"))
self.end_layer = int(getattr(self.computation, "end_layer"))
self.total_layers = int(getattr(self.computation, "total_layers"))
self.role = role_for_range(
self.start_layer, self.end_layer, self.total_layers
)
@property
def is_head(self) -> bool:
return self.role.owns_embedding
@property
def is_tail(self) -> bool:
return self.role.owns_final_head
def forward(
self,
*,
token_ids: Any | None = None,
boundary: BoundaryBundle | None = None,
) -> BoundaryBundle | TailOutput:
"""Run one prefill/decode pass for this range and emit its boundary output.
Head/full ranges require ``token_ids``; middle/tail ranges require the
``boundary`` bundle. Non-tail ranges return a :class:`BoundaryBundle`;
tail/full ranges return a :class:`TailOutput` through the sampling
contract.
"""
hidden, positions = self._ingest(token_ids, boundary)
hidden = self.computation.run_layers(hidden, positions=positions)
if self.is_tail:
return self._emit_tail(hidden)
return self._emit_boundary(hidden, positions)
# -- input side -----------------------------------------------------------
def _ingest(
self, token_ids: Any | None, boundary: BoundaryBundle | None
) -> tuple[np.ndarray, np.ndarray]:
if self.role.owns_embedding:
return self._ingest_tokens(token_ids, boundary)
return self._ingest_boundary(token_ids, boundary)
def _ingest_tokens(
self, token_ids: Any | None, boundary: BoundaryBundle | None
) -> tuple[np.ndarray, np.ndarray]:
if token_ids is None:
raise BoundaryContractError(
"the head owns token embedding and must receive token IDs"
)
if boundary is not None:
raise BoundaryContractError(
"the head owns token embedding; it must not receive a boundary "
"bundle from an upstream range"
)
ids = np.asarray(token_ids)
if ids.ndim == 1:
ids = ids[None, :]
if ids.ndim != 2:
raise BoundaryContractError("token IDs must be (seq,) or (batch, seq)")
hidden = np.asarray(self.computation.embed_tokens(ids))
positions = np.broadcast_to(
np.arange(ids.shape[1], dtype=np.int64), ids.shape
).copy()
return hidden, positions
def _ingest_boundary(
self, token_ids: Any | None, boundary: BoundaryBundle | None
) -> tuple[np.ndarray, np.ndarray]:
if token_ids is not None:
raise BoundaryContractError(
"middle/tail Shards bypass token embedding; they must not receive "
"token IDs"
)
if boundary is None:
raise BoundaryContractError(
"middle/tail Shards must receive the named boundary bundle"
)
self._check_boundary(boundary)
return np.asarray(boundary.residual), np.asarray(boundary.positions)
def _check_boundary(self, boundary: BoundaryBundle) -> None:
if certified_architecture(boundary.architecture_adapter) is not self.architecture:
raise BoundaryContractError(
f"boundary bundle architecture {boundary.architecture_adapter!r} "
f"does not match this Shard's adapter {self.architecture.adapter!r}"
)
if boundary.schema_version != self.architecture.boundary_schema_version:
raise BoundaryContractError(
f"boundary schema v{boundary.schema_version} is not supported by "
f"this Shard (expects v{self.architecture.boundary_schema_version})"
)
if boundary.tensor_name != self.architecture.boundary_tensor_name:
raise BoundaryContractError(
f"boundary tensor {boundary.tensor_name!r} is not the "
f"architecture-defined {self.architecture.boundary_tensor_name!r}"
)
if boundary.normalized:
raise BoundaryContractError(
"boundary bundle is normalized; a Shard range must receive the "
"UNNORMALIZED architecture-defined residual"
)
if boundary.next_layer != self.start_layer:
raise BoundaryContractError(
f"boundary hands over at layer {boundary.next_layer} but this "
f"Shard starts at layer {self.start_layer}"
)
# -- output side ----------------------------------------------------------
def _emit_boundary(
self, hidden: np.ndarray, positions: np.ndarray
) -> BoundaryBundle:
# A non-tail Shard emits the unnormalized residual with every position row
# intact: no final norm, no LM head, no tail-only row pruning. next_layer
# is the receiver's overlap-safe effective start.
return BoundaryBundle(
architecture_adapter=self.architecture.adapter,
schema_version=self.architecture.boundary_schema_version,
tensor_name=self.architecture.boundary_tensor_name,
residual=np.asarray(hidden),
positions=np.asarray(positions),
next_layer=self.end_layer + 1,
normalized=False,
)
def _emit_tail(self, hidden: np.ndarray) -> TailOutput:
hidden = np.asarray(hidden)
# Tail-only row pruning: only the final position is needed to sample the
# next token, so the LM head runs on the pruned row. A non-tail Shard is
# forbidden from doing this (it must forward every row).
if self.architecture.prunes_rows_at_tail:
last_hidden = hidden[:, -1:, :]
else: # pragma: no cover - no certified architecture takes this path yet
last_hidden = hidden
if self.architecture.normalizes_before_head:
last_hidden = np.asarray(self.computation.final_norm(last_hidden))
logits = np.asarray(self.computation.lm_head(last_hidden))
last_logits = logits[:, -1, :]
token_id = self.sampling.sample(last_logits)
return TailOutput(
token_id=token_id, logits=last_logits, sampling=self.sampling
)
def _byte_order(dtype: np.dtype) -> str:
order = dtype.byteorder
if order == "<":
return "little"
if order == ">":
return "big"
# '=' native, '|' not applicable (single byte)
import sys
return sys.byteorder if order in ("=", "|") else "little"
def _array_from_wire(field_payload: dict[str, Any]) -> np.ndarray:
array = np.frombuffer(
field_payload["data"], dtype=np.dtype(field_payload["dtype"])
)
return array.reshape(field_payload["shape"]).copy()