AstrAI/astrai/model/components/decoder_block.py

40 lines
1.2 KiB
Python

from dataclasses import asdict
from typing import Optional
import torch.nn as nn
from torch import Tensor
from astrai.inference.core.cache import CacheView
from astrai.model.components.attention import AttnFactory
from astrai.model.components.mlp import FFNFactory
from astrai.model.components.norm import RMSNorm
class DecoderBlock(nn.Module):
def __init__(self, config, layer_id: int):
super().__init__()
cfg = asdict(config)
cfg["down_init_std"] = 0.02 / (2 * config.n_layers) ** 0.5
self.attention = AttnFactory.create(config.attn_type, **cfg, layer_id=layer_id)
self.input_norm = RMSNorm(config.dim, config.norm_eps)
self.post_attention_norm = RMSNorm(config.dim, config.norm_eps)
self.mlp = FFNFactory.create(config.ffn_type, **cfg)
def forward(
self,
x: Tensor,
rotary_emb: Tensor,
attention_mask: Optional[Tensor] = None,
paged_cache: Optional[CacheView] = None,
) -> Tensor:
attn_output = self.attention(
self.input_norm(x),
rotary_emb,
attention_mask,
paged_cache,
)
x = attn_output + x
x = self.mlp(self.post_attention_norm(x)) + x
return x