781 lines
34 KiB
Python
781 lines
34 KiB
Python
import math
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import struct
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import inspect
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import time
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from .LMConfig import LMConfig
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from typing import Any, Optional, Tuple, List, Union
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import numpy as np
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import torch
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import torch.nn.functional as F
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from torch import nn
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from transformers import PreTrainedModel
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from transformers.modeling_outputs import CausalLMOutputWithPast
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from torch import nn, einsum
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from einops import rearrange, repeat
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def exists(val):
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return val is not None
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# RMSNorm 类定义了一个用于归一化输入张量的模块。
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class RMSNorm(torch.nn.Module):
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def __init__(self, dim: int, eps: float = 1e-6):
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super().__init__()
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self.eps = eps
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self.weight = nn.Parameter(torch.ones(dim))
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def _norm(self, x):
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return x * torch.rsqrt(x.pow(2).mean(-1, keepdim=True) + self.eps)
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def forward(self, x):
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return self.weight * self._norm(x.float()).type_as(x)
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# precompute_pos_cis 函数用于预计算位置编码（复数版本）。
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def precompute_pos_cis(dim: int, end: int = int(32 * 1024), theta: float = 1e6):
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freqs = 1.0 / (theta ** (torch.arange(0, dim, 2)[: (dim // 2)].float() / dim))
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t = torch.arange(end, device=freqs.device) # type: ignore
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freqs = torch.outer(t, freqs).float() # type: ignore
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pos_cis = torch.polar(torch.ones_like(freqs), freqs) # complex64
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return pos_cis
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# apply_rotary_emb 函数用于应用旋转位置编码（复数版本）。
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def apply_rotary_emb(xq, xk, pos_cis):
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def unite_shape(pos_cis, x):
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ndim = x.ndim
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assert 0 <= 1 < ndim
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assert pos_cis.shape == (x.shape[1], x.shape[-1])
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shape = [d if i == 1 or i == ndim - 1 else 1 for i, d in enumerate(x.shape)]
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return pos_cis.view(*shape)
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xq_ = torch.view_as_complex(xq.float().reshape(*xq.shape[:-1], -1, 2))
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xk_ = torch.view_as_complex(xk.float().reshape(*xk.shape[:-1], -1, 2))
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pos_cis = unite_shape(pos_cis, xq_)
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xq_out = torch.view_as_real(xq_ * pos_cis).flatten(3)
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xk_out = torch.view_as_real(xk_ * pos_cis).flatten(3)
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return xq_out.type_as(xq), xk_out.type_as(xk)
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# precompute_pos_cis_real 函数用于预计算位置编码（实数版本）。
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def precompute_pos_cis_real(dim: int, end: int = int(32 * 1024), theta: float = 1e6):
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"""使用实数张量实现位置编码，避免使用复数张量
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这个函数与precompute_pos_cis完全等价，但使用实数张量而非复数张量。
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原始函数生成形状为[seq_len, dim//2]的复数张量，其中实部全为1，虚部为旋转角度。
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这个函数生成形状为[seq_len, dim]的实数张量，其中偶数索引是cos(角度)，奇数索引是sin(角度)。
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"""
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# 确保dim是偶数
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if dim % 2 != 0:
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raise ValueError(f"维度必须是偶数，但得到了 {dim}")
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# 复制原始函数的频率计算逻辑
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freqs = 1.0 / (theta ** (torch.arange(0, dim, 2)[: (dim // 2)].float() / dim))
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t = torch.arange(end, device=freqs.device)
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freqs = torch.outer(t, freqs).float()
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# 计算cos和sin值
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# 在复数版本中，pos_cis = torch.polar(torch.ones_like(freqs), freqs)
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# 等价于 cos(freqs) + i*sin(freqs)
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cos = torch.cos(freqs)
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sin = torch.sin(freqs)
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# 创建实数张量，交错排列cos和sin
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pos_emb = torch.zeros((end, dim), device=freqs.device)
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pos_emb[:, 0::2] = cos # 偶数索引放cos
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pos_emb[:, 1::2] = sin # 奇数索引放sin
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return pos_emb
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# apply_rotary_emb_real 函数用于应用旋转位置编码（实数版本）。
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def apply_rotary_emb_real(xq, xk, pos_emb):
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"""使用实数张量实现旋转位置编码，避免使用复数张量
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这个函数与apply_rotary_emb完全等价，但使用实数张量而非复数张量。
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原始函数将输入张量转换为复数形式，与位置编码相乘，然后再转回实数形式。
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这个函数直接使用实数运算实现相同的旋转操作。
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"""
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# 获取形状信息
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bsz, seq_len, n_heads, head_dim = xq.shape
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# 确保pos_emb形状正确
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assert pos_emb.shape[0] >= seq_len, f"位置编码长度 {pos_emb.shape[0]} 小于序列长度 {seq_len}"
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assert pos_emb.shape[1] == head_dim, f"位置编码维度 {pos_emb.shape[1]} 与头维度 {head_dim} 不匹配"
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# 截取需要的位置编码长度
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pos_emb = pos_emb[:seq_len]
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# 将pos_emb调整为广播形状 [1, seq_len, 1, head_dim]
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pos_emb = pos_emb.unsqueeze(0).unsqueeze(2)
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# 将head_dim分成两半
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half_head_dim = head_dim // 2
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# 提取cos和sin值（偶数索引是cos，奇数索引是sin）
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cos = pos_emb[..., 0::2]
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sin = pos_emb[..., 1::2]
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# 将xq和xk重新排列，以便进行旋转操作
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# 原始复数版本中，xq和xk被重塑为复数张量，其中实部和虚部交错排列
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# 在实数版本中，我们需要将偶数索引和奇数索引分开处理
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# 分离偶数和奇数索引
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xq_even = xq[..., 0::2] # 偶数索引，对应复数的实部
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xq_odd = xq[..., 1::2] # 奇数索引，对应复数的虚部
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xk_even = xk[..., 0::2]
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xk_odd = xk[..., 1::2]
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# 应用旋转（等价于复数乘法）
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# (a + bi)(cos + sin*i) = (a*cos - b*sin) + (a*sin + b*cos)i
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# 其中a是偶数索引，b是奇数索引
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xq_out_even = xq_even * cos - xq_odd * sin # 新的偶数索引（实部）
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xq_out_odd = xq_even * sin + xq_odd * cos # 新的奇数索引（虚部）
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xk_out_even = xk_even * cos - xk_odd * sin
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xk_out_odd = xk_even * sin + xk_odd * cos
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# 重新组合偶数和奇数索引
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xq_out = torch.zeros_like(xq)
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xk_out = torch.zeros_like(xk)
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xq_out[..., 0::2] = xq_out_even
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xq_out[..., 1::2] = xq_out_odd
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xk_out[..., 0::2] = xk_out_even
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xk_out[..., 1::2] = xk_out_odd
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return xq_out.type_as(xq), xk_out.type_as(xk)
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# repeat_kv 函数用于重复键值对。
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def repeat_kv(x: torch.Tensor, n_rep: int) -> torch.Tensor:
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"""torch.repeat_interleave(x, dim=2, repeats=n_rep)"""
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bs, slen, n_kv_heads, head_dim = x.shape
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if n_rep == 1:
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return x
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return (
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x[:, :, :, None, :]
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.expand(bs, slen, n_kv_heads, n_rep, head_dim)
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.reshape(bs, slen, n_kv_heads * n_rep, head_dim)
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)
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class Attention(nn.Module):
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def __init__(self, args: LMConfig):
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super().__init__()
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self.n_kv_heads = args.n_heads if args.n_kv_heads is None else args.n_kv_heads
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assert args.n_heads % self.n_kv_heads == 0
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self.n_local_heads = args.n_heads
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self.n_local_kv_heads = self.n_kv_heads
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self.n_rep = self.n_local_heads // self.n_local_kv_heads
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self.head_dim = args.dim // args.n_heads
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self.wq = nn.Linear(args.dim, args.n_heads * self.head_dim, bias=False)
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self.wk = nn.Linear(args.dim, self.n_kv_heads * self.head_dim, bias=False)
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self.wv = nn.Linear(args.dim, self.n_kv_heads * self.head_dim, bias=False)
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self.wo = nn.Linear(args.n_heads * self.head_dim, args.dim, bias=False)
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self.attn_dropout = nn.Dropout(args.dropout)
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self.resid_dropout = nn.Dropout(args.dropout)
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self.dropout = args.dropout
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self.flash = hasattr(torch.nn.functional, 'scaled_dot_product_attention') and args.flash_attn
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# print("WARNING: using slow attention. Flash Attention requires PyTorch >= 2.0")
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mask = torch.full((1, 1, args.max_seq_len, args.max_seq_len), float("-inf"))
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mask = torch.triu(mask, diagonal=1)
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self.register_buffer("mask", mask, persistent=False)
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def forward(self,
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x: torch.Tensor,
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pos_cis: torch.Tensor,
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db_value=None):
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bsz, seq_len, _ = x.shape #bsz: 批量大小, seq_len: 序列长度, _: 隐藏维度
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xq, xk, xv = self.wq(x), self.wk(x), self.wv(x) #将输入张量x分别通过线性层wq, wk, wv进行变换，得到查询、键和值。
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xq = xq.view(bsz, seq_len, self.n_local_heads, self.head_dim) #将变换后的张量xq重塑为形状为(bsz, seq_len, n_local_heads, head_dim)的形状。
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xk = xk.view(bsz, seq_len, self.n_local_kv_heads, self.head_dim) #将变换后的张量xk重塑为形状为(bsz, seq_len, n_local_kv_heads, head_dim)的形状。
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xv = xv.view(bsz, seq_len, self.n_local_kv_heads, self.head_dim) #将变换后的张量xv重塑为形状为(bsz, seq_len, n_local_kv_heads, head_dim)的形状。
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# 应用旋转位置编码（使用实数版本）
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xq, xk = apply_rotary_emb_real(xq, xk, pos_cis)
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# kv_cache实现 REMOVED
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# if past_key_value is not None:
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# xk = torch.cat([past_key_value[0], xk], dim=1)
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# xv = torch.cat([past_key_value[1], xv], dim=1)
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# past_kv = (xk, xv) if use_cache else None
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# 重复键值对
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xq, xk, xv = (
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xq.transpose(1, 2),
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repeat_kv(xk, self.n_rep).transpose(1, 2),
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repeat_kv(xv, self.n_rep).transpose(1, 2)
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)
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# 如果提供了db_value，根据头的数量调整它的形状并与xv合并
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if db_value is not None:
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# 确保db_value的形状与xv兼容，假设db_value形状为[B, N, H, D]
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if db_value.ndim == 4: # [B, N, H, D]
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db_value = db_value.transpose(1, 2) # -> [B, H, N, D]
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# 检查是否需要调整D维度
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if db_value.shape[-1] != xv.shape[-1]:
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# 如果db_value的维度与xv不同，可以添加一个投影层
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# 或者在这里使用简单的调整方法
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# 这里我们简单地通过均值池化或重复来调整维度
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if db_value.shape[-1] > xv.shape[-1]:
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# 降维
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factor = db_value.shape[-1] // xv.shape[-1]
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db_value = db_value.view(bsz, self.n_local_heads, seq_len, factor, xv.shape[-1])
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db_value = db_value.mean(dim=3)
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else:
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# 升维
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factor = xv.shape[-1] // db_value.shape[-1]
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db_value = db_value.unsqueeze(-1).repeat(1, 1, 1, 1, factor)
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db_value = db_value.view(bsz, self.n_local_heads, seq_len, xv.shape[-1])
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# 将db_value与xv相加或融合
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# 这里我们简单地将它们相加，但你也可以使用其他融合方法
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xv = xv + db_value
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# 使用Flash Attention
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if self.flash and seq_len != 1:
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dropout_p = self.dropout if self.training else 0.0
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output = F.scaled_dot_product_attention(
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xq, xk, xv,
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attn_mask=None,
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dropout_p=dropout_p,
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is_causal=True
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)
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else:
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scores = (xq @ xk.transpose(-2, -1)) / math.sqrt(self.head_dim)
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scores += self.mask[:, :, :seq_len, :seq_len]
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scores = F.softmax(scores.float(), dim=-1).type_as(xq)
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scores = self.attn_dropout(scores)
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output = scores @ xv
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output = output.transpose(1, 2).reshape(bsz, seq_len, -1)
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output = self.resid_dropout(self.wo(output))
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return output
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class CrossAttention(nn.Module):
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def __init__(
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self,
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config
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):
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super().__init__()
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self.config = config
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self.num_heads = 8
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self.head_dim = self.config.dim // self.num_heads
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self.to_q = nn.Linear(self.config.dim, self.config.dim, bias=False)
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self.to_k = nn.Linear(self.config.dim, self.config.dim, bias=False)
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self.to_v = nn.Linear(self.config.dim, self.config.dim, bias=False)
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self.to_out = nn.Linear(self.config.dim, self.config.dim, bias=False)
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def forward(self, x, db, context_mask=None, pos_emb=None):
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batch_size = x.size(0)
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# 分离多头
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q = self.to_q(x).view(batch_size, -1, self.num_heads, self.head_dim).transpose(1, 2)
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k = self.to_k(db).view(batch_size, -1, self.num_heads, self.head_dim).transpose(1, 2)
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v = self.to_v(db).view(batch_size, -1, self.num_heads, self.head_dim).transpose(1, 2)
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if pos_emb is not None:
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pos_emb = pos_emb.view(batch_size, -1, self.num_heads, self.head_dim).transpose(1, 2)
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q = q + pos_emb
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k = k + pos_emb
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v = v + pos_emb
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attn_scores = torch.matmul(q, k.transpose(-2, -1)) / math.sqrt(self.head_dim)
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if context_mask is not None:
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expanded_mask = context_mask.unsqueeze(1).expand(-1, self.num_heads, -1, -1)
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attn_scores = attn_scores.masked_fill(expanded_mask == 0, -1e10)
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attn_weights = F.softmax(attn_scores, dim=-1)
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context = torch.matmul(attn_weights, v)
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context = context.transpose(1, 2).contiguous().view(batch_size, -1, self.config.dim)
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context = self.to_out(context)
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return context
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class FeedForward(nn.Module):
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def __init__(self, config: LMConfig):
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super().__init__()
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if config.hidden_dim is None:
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hidden_dim = 4 * config.dim
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hidden_dim = int(2 * hidden_dim / 3)
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config.hidden_dim = config.multiple_of * ((hidden_dim + config.multiple_of - 1) // config.multiple_of)
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self.w1 = nn.Linear(config.dim, config.hidden_dim, bias=False)
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self.w2 = nn.Linear(config.hidden_dim, config.dim, bias=False)
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self.w3 = nn.Linear(config.dim, config.hidden_dim, bias=False)
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self.dropout = nn.Dropout(config.dropout)
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def forward(self, x):
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return self.dropout(self.w2(F.silu(self.w1(x)) * self.w3(x)))
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class MoEGate(nn.Module):
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def __init__(self, config: LMConfig):
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super().__init__()
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self.config = config
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self.top_k = config.num_experts_per_tok
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self.n_routed_experts = config.n_routed_experts
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self.scoring_func = config.scoring_func
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self.alpha = config.aux_loss_alpha
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self.seq_aux = config.seq_aux
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self.norm_topk_prob = config.norm_topk_prob
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self.gating_dim = config.dim
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self.weight = nn.Parameter(torch.empty((self.n_routed_experts, self.gating_dim)))
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self.reset_parameters()
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def reset_parameters(self) -> None:
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import torch.nn.init as init
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init.kaiming_uniform_(self.weight, a=math.sqrt(5))
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def forward(self, hidden_states):
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bsz, seq_len, h = hidden_states.shape
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hidden_states = hidden_states.view(-1, h)
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logits = F.linear(hidden_states, self.weight, None)
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if self.scoring_func == 'softmax':
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scores = logits.softmax(dim=-1)
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else:
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raise NotImplementedError(f'insupportable scoring function for MoE gating: {self.scoring_func}')
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topk_weight, topk_idx = torch.topk(scores, k=self.top_k, dim=-1, sorted=False)
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if self.top_k > 1 and self.norm_topk_prob:
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denominator = topk_weight.sum(dim=-1, keepdim=True) + 1e-20
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topk_weight = topk_weight / denominator
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if self.training and self.alpha > 0.0:
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scores_for_aux = scores
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aux_topk = self.top_k
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topk_idx_for_aux_loss = topk_idx.view(bsz, -1)
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if self.seq_aux:
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scores_for_seq_aux = scores_for_aux.view(bsz, seq_len, -1)
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ce = torch.zeros(bsz, self.n_routed_experts, device=hidden_states.device)
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ce.scatter_add_(1, topk_idx_for_aux_loss,
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torch.ones(bsz, seq_len * aux_topk, device=hidden_states.device)).div_(
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seq_len * aux_topk / self.n_routed_experts)
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aux_loss = (ce * scores_for_seq_aux.mean(dim=1)).sum(dim=1).mean() * self.alpha
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else:
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mask_ce = F.one_hot(topk_idx_for_aux_loss.view(-1), num_classes=self.n_routed_experts)
|
||
ce = mask_ce.float().mean(0)
|
||
Pi = scores_for_aux.mean(0)
|
||
fi = ce * self.n_routed_experts
|
||
aux_loss = (Pi * fi).sum() * self.alpha
|
||
else:
|
||
aux_loss = 0
|
||
return topk_idx, topk_weight, aux_loss
|
||
|
||
|
||
class MOEFeedForward(nn.Module):
|
||
def __init__(self, config: LMConfig):
|
||
super().__init__()
|
||
self.config = config
|
||
self.experts = nn.ModuleList([
|
||
FeedForward(config)
|
||
for _ in range(config.n_routed_experts)
|
||
])
|
||
self.gate = MoEGate(config)
|
||
if config.n_shared_experts is not None:
|
||
self.shared_experts = FeedForward(config)
|
||
|
||
def forward(self, x):
|
||
identity = x
|
||
orig_shape = x.shape
|
||
bsz, seq_len, _ = x.shape
|
||
# 使用门控机制选择专家
|
||
topk_idx, topk_weight, aux_loss = self.gate(x)
|
||
x = x.view(-1, x.shape[-1])
|
||
flat_topk_idx = topk_idx.view(-1)
|
||
if self.training:
|
||
x = x.repeat_interleave(self.config.num_experts_per_tok, dim=0)
|
||
y = torch.empty_like(x, dtype=torch.float16)
|
||
for i, expert in enumerate(self.experts):
|
||
y[flat_topk_idx == i] = expert(x[flat_topk_idx == i]).to(y.dtype) # 确保类型一致
|
||
y = (y.view(*topk_weight.shape, -1) * topk_weight.unsqueeze(-1)).sum(dim=1)
|
||
y = y.view(*orig_shape)
|
||
else:
|
||
y = self.moe_infer(x, flat_topk_idx, topk_weight.view(-1, 1)).view(*orig_shape)
|
||
if self.config.n_shared_experts is not None:
|
||
y = y + self.shared_experts(identity)
|
||
self.aux_loss = aux_loss
|
||
return y
|
||
|
||
@torch.no_grad()
|
||
def moe_infer(self, x, flat_expert_indices, flat_expert_weights):
|
||
expert_cache = torch.zeros_like(x)
|
||
idxs = flat_expert_indices.argsort()
|
||
tokens_per_expert = flat_expert_indices.bincount().cpu().numpy().cumsum(0)
|
||
token_idxs = idxs // self.config.num_experts_per_tok
|
||
# 当tokens_per_expert = [6, 15, 20, 26]，tokens_per_expert.shape[0]即为专家数量（此时为4）
|
||
# 且token_idxs = [3, 7, 19, 21, 24, 25, 4, 5, 6, 10, 11, 12...] 时
|
||
# 意味token_idxs[:6] -> [3, 7, 19, 21, 24, 25]这6个位置属于专家0处理的token（每个token有可能被多个专家处理，这取决于num_experts_per_tok）
|
||
# 接下来9个位置token_idxs[6:15] -> [4, 5, 6, 10, 11, 12...]属于专家1处理的token...依此类推
|
||
for i, end_idx in enumerate(tokens_per_expert):
|
||
start_idx = 0 if i == 0 else tokens_per_expert[i - 1]
|
||
if start_idx == end_idx:
|
||
continue
|
||
expert = self.experts[i]
|
||
exp_token_idx = token_idxs[start_idx:end_idx]
|
||
expert_tokens = x[exp_token_idx]
|
||
expert_out = expert(expert_tokens).to(expert_cache.dtype)
|
||
expert_out.mul_(flat_expert_weights[idxs[start_idx:end_idx]])
|
||
expert_cache.scatter_add_(0, exp_token_idx.view(-1, 1).repeat(1, x.shape[-1]), expert_out)
|
||
|
||
return expert_cache
|
||
|
||
|
||
class MiniMindBlock(nn.Module):
|
||
def __init__(self, layer_id: int, config: LMConfig):
|
||
super().__init__()
|
||
self.n_heads = config.n_heads
|
||
self.dim = config.dim
|
||
self.head_dim = config.dim // config.n_heads
|
||
self.attention = Attention(config)
|
||
self.cross_att = CrossAttention(config)
|
||
|
||
self.layer_id = layer_id
|
||
self.attention_norm = RMSNorm(config.dim, eps=config.norm_eps)
|
||
self.ffn_norm = RMSNorm(config.dim, eps=config.norm_eps)
|
||
self.feed_forward = FeedForward(config) if not config.use_moe else MOEFeedForward(config)
|
||
|
||
# 假设num_experts是已定义的总专家数量的平方根
|
||
|
||
|
||
# 查询生成的参数
|
||
|
||
|
||
# 创建查询生成模块
|
||
# if weight_down_embed is not None:
|
||
# self.to_queries = nn.Sequential(
|
||
# nn.Linear(config.dim, self.dim_key * 2, bias=False),
|
||
# # nn.Unflatten(2, (2, self.n_heads, self.dim_key)) # 替代Rearrange
|
||
# )
|
||
|
||
# # 超参数
|
||
# self.product_key_topk = min(16, self.num_keys) # 确保不超过num_keys
|
||
# self.num_experts_per_head_topk = 1 # 最终每个头选取的专家数
|
||
|
||
def forward(self, x, db_value, pos_cis):
|
||
# import pdb;pdb.set_trace()
|
||
# db_value = None
|
||
|
||
# # 如果有weight_down_embed，使用Product Key机制
|
||
# if self.weight_down_embed is not None:
|
||
# # 1. 生成queries
|
||
# batch_size, seq_len, dim = x.shape
|
||
|
||
# # collapse sequence dimension by averaging
|
||
# x_flat = x.mean(dim=1) # [batch_size, dim]
|
||
# queries = self.to_queries(x_flat) # [batch_size, 2*dim_key]
|
||
# queries = queries.reshape(batch_size, 2, self.dim_key) # [batch_size, 2, dim_key]
|
||
# queries = queries.permute(1, 0, 2) # [2, batch_size, dim_key]
|
||
|
||
# # 2. 计算queries与keys的相似度
|
||
# sim = torch.einsum('p b d, k p d -> p b k', queries, self.keys)
|
||
|
||
# # 3. 在两个子空间分别做top-k
|
||
# scores_and_indices = [sim[p].topk(self.product_key_topk, dim=-1) for p in range(2)]
|
||
# scores_x, scores_y = scores_and_indices[0][0], scores_and_indices[1][0]
|
||
# indices_x, indices_y = scores_and_indices[0][1], scores_and_indices[1][1]
|
||
|
||
# # 4. 组合两个子空间的分数和索引
|
||
# all_scores = scores_x.unsqueeze(-1) + scores_y.unsqueeze(-2)
|
||
# all_scores = all_scores.view(*all_scores.shape[:-2], -1)
|
||
|
||
# all_indices = (indices_x.unsqueeze(-1) * self.num_keys) + indices_y.unsqueeze(-2)
|
||
# all_indices = all_indices.view(*all_indices.shape[:-2], -1)
|
||
|
||
# # 5. 最终top-k选择
|
||
# scores, pk_indices = all_scores.topk(self.num_experts_per_head_topk, dim=-1)
|
||
# indices = all_indices.gather(-1, pk_indices)
|
||
|
||
# # 6. 从embedding中获取专家值
|
||
|
||
# # 从embedding中获取值
|
||
# flat_indices = indices.view(-1) # 将索引展平为一维张量
|
||
# db_values = self.weight_down_embed(flat_indices)
|
||
|
||
# # 重塑回原始形状
|
||
# db_value = db_values.view(batch_size, -1, dim)
|
||
|
||
|
||
# 注意力计算
|
||
h_attn = self.attention(
|
||
self.attention_norm(x),
|
||
pos_cis,
|
||
db_value=db_value
|
||
)
|
||
|
||
h_attn = self.cross_att(h_attn, db_value)
|
||
|
||
# 残差连接
|
||
h = x + h_attn
|
||
|
||
# 前馈神经网络
|
||
out = h + self.feed_forward(self.ffn_norm(h))
|
||
return out
|
||
|
||
class ExtractDB(nn.Module):
|
||
def __init__(self,params):
|
||
# 修改专家数量和知识维度，确保能开方
|
||
super().__init__()
|
||
self.batch_size = None
|
||
self.dim = params.dim
|
||
self.dim_key = self.dim // 2
|
||
self.knowledge_num = params.knowledge_num # 100专家，确保是完全平方数
|
||
# 将knowledge_dim设置为与head_dim相同，以便在attention中直接使用
|
||
self.head_dim = params.dim // params.n_heads
|
||
self.knowledge_length = params.knowledge_length
|
||
|
||
# 使用register_buffer代替nn.Parameter，避免梯度问题
|
||
# self.register_buffer('weight_down_embed', torch.randn(self.knowledge_num, self.knowledge_length) * 0.02)
|
||
self.register_buffer('weight_down_embed',torch.randint(low=0,high=6400, size=(self.knowledge_num, self.knowledge_length),dtype=torch.long))
|
||
|
||
|
||
|
||
|
||
self.num_keys = int(math.sqrt(self.knowledge_num)) if self.knowledge_num > 0 else 0
|
||
self.product_key_topk = min(16, self.num_keys)
|
||
self.keys = nn.Parameter(torch.randn(self.num_keys, 2, self.dim_key) * 0.02)
|
||
self.num_experts_per_head_topk = 1
|
||
self.to_queries = nn.Sequential(
|
||
nn.Linear(params.dim, self.dim_key * 2, bias=False),
|
||
)
|
||
|
||
def q_to_k(self,x):
|
||
# 1. 生成queries
|
||
self.batch_size, seq_len, dim = x.shape
|
||
|
||
# collapse sequence dimension by averaging
|
||
x_flat = x.mean(dim=1) # [batch_size, dim]
|
||
|
||
queries = self.to_queries(x_flat) # [batch_size, 2*dim_key]
|
||
queries = queries.reshape(self.batch_size, 2, self.dim_key) # [batch_size, 2, dim_key]
|
||
queries = queries.permute(1, 0, 2) # [2, batch_size, dim_key]
|
||
|
||
# 2. 计算queries与keys的相似度
|
||
sim = torch.einsum('p b d, k p d -> p b k', queries, self.keys)
|
||
|
||
# 3. 在两个子空间分别做top-k
|
||
scores_and_indices = [sim[p].topk(self.product_key_topk, dim=-1) for p in range(2)]
|
||
scores_x, scores_y = scores_and_indices[0][0], scores_and_indices[1][0]
|
||
indices_x, indices_y = scores_and_indices[0][1], scores_and_indices[1][1]
|
||
|
||
# 4. 组合两个子空间的分数和索引
|
||
all_scores = scores_x.unsqueeze(-1) + scores_y.unsqueeze(-2)
|
||
all_scores = all_scores.view(*all_scores.shape[:-2], -1)
|
||
|
||
all_indices = (indices_x.unsqueeze(-1) * self.num_keys) + indices_y.unsqueeze(-2)
|
||
all_indices = all_indices.view(*all_indices.shape[:-2], -1)
|
||
|
||
# 5. 最终top-k选择
|
||
scores, pk_indices = all_scores.topk(self.num_experts_per_head_topk, dim=-1)
|
||
indices = all_indices.gather(-1, pk_indices)
|
||
flat_indices = indices.view(-1)
|
||
return flat_indices
|
||
|
||
def get_data(self, index):
|
||
# 直接从GPU获取embedding
|
||
db_values = self.weight_down_embed[index]#变成token了所以是1,后续再过emb
|
||
# db_value = db_values.view(self.batch_size,-1)
|
||
return db_values
|
||
|
||
@torch.no_grad()
|
||
def updata_value(self, k, v):#要加一个从向量返回index的过程
|
||
# 直接更新buffer上的值 (不需要梯度)
|
||
v_reshaped = v.view(v.size(0), -1)
|
||
# 确保数据类型匹配
|
||
v_reshaped = v_reshaped.to(dtype=self.weight_down_embed.dtype)
|
||
self.weight_down_embed[k] = v_reshaped
|
||
|
||
|
||
|
||
class MiniMindLM(PreTrainedModel):
|
||
config_class = LMConfig
|
||
|
||
def __init__(self, params: LMConfig = None):
|
||
self.params = params or LMConfig()
|
||
super().__init__(self.params)
|
||
self.vocab_size, self.n_layers = params.vocab_size, params.n_layers
|
||
self.tok_embeddings = nn.Embedding(params.vocab_size, params.dim)
|
||
self.dropout = nn.Dropout(params.dropout)
|
||
# 移除旧的weight_down_embed声明
|
||
self.extract_db = ExtractDB(self.params)
|
||
|
||
# 将self.weight_down_embed传递给每个MiniMindBlock
|
||
self.layers = nn.ModuleList([MiniMindBlock(l, params) for l in range(self.n_layers)])
|
||
self.norm = RMSNorm(params.dim, eps=params.norm_eps)
|
||
self.output = nn.Linear(params.dim, params.vocab_size, bias=False)
|
||
self.database_output = nn.Linear(params.dim, params.knowledge_length, bias=False)
|
||
self.tok_embeddings.weight = self.output.weight
|
||
self.database_output.weight = self.output.weight
|
||
|
||
# Calculate input dimension
|
||
input_dim = (self.params.max_seq_len-1)*self.params.n_layers
|
||
# Use a bottleneck architecture to reduce parameters
|
||
bottleneck_dim = 256 # Significantly smaller bottleneck dimension
|
||
|
||
# Factorized shared downsampling using two smaller convolutions
|
||
self.shared_downsample = nn.Sequential(
|
||
# First reduce input dimension to bottleneck
|
||
nn.Conv1d(input_dim, bottleneck_dim, kernel_size=1, padding='same'),
|
||
nn.ReLU(), # Non-linearity to improve representation capacity
|
||
# Then expand to target dimension
|
||
nn.Conv1d(bottleneck_dim, 128*8, kernel_size=1, padding='same')
|
||
)
|
||
|
||
# Specific layers for v path
|
||
self.downsample_v_specific = nn.Sequential(
|
||
nn.Conv1d(128*8, 128, kernel_size=1, padding='same'),
|
||
nn.Conv1d(128, self.params.knowledge_length, kernel_size=1, padding='same')
|
||
)
|
||
|
||
# Specific layers for q path
|
||
self.downsample_q_specific = nn.Sequential(
|
||
nn.Conv1d(128*8, 512, kernel_size=1, padding='same')
|
||
)
|
||
# 使用实数版本的位置编码，避免复数张量可能导致的段错误
|
||
self.register_buffer("pos_cis_real",
|
||
precompute_pos_cis_real(dim=params.dim // params.n_heads, theta=params.rope_theta),
|
||
persistent=False)
|
||
self.params = params
|
||
|
||
def forward(self,
|
||
input_ids: Optional[torch.Tensor] = None,
|
||
logits_to_keep: Union[int, torch.Tensor] = 0,
|
||
**args):
|
||
start_pos = args.get('start_pos', 0)
|
||
h = self.dropout(self.tok_embeddings(input_ids))
|
||
pos_cis_real = self.pos_cis_real[start_pos:start_pos + input_ids.size(1)]
|
||
h_list = []
|
||
|
||
for l, layer in enumerate(self.layers):
|
||
# 禁用数据库模式，使用固定值替代数据库查询
|
||
if self.params.disable_db:
|
||
# 创建一个形状为[batch_size, n_layers, dim]的tensor，所有元素值为1e-4
|
||
batch_size = h.size(0)
|
||
db_value = torch.full((batch_size, self.n_layers, self.params.dim), 1e-4,
|
||
dtype=h.dtype, device=h.device)
|
||
else:
|
||
# 正常模式，使用数据库查询
|
||
# import pdb;pdb.set_trace()
|
||
index = self.extract_db.q_to_k(h)
|
||
|
||
token_idx = self.extract_db.get_data(index) #这里是index
|
||
|
||
db_value =self.tok_embeddings(token_idx)
|
||
|
||
h = layer(
|
||
h, db_value, pos_cis_real
|
||
)
|
||
|
||
h_list.append(h.unsqueeze(0))
|
||
|
||
h_tensor = torch.cat(h_list, dim=0).permute(1, 0, 2, 3)
|
||
|
||
# 只在非禁用数据库模式下执行数据库更新逻辑
|
||
if not self.params.disable_db:
|
||
# 使用detach()分离计算图，避免多次反向传播
|
||
h_tensor_detached = h_tensor.detach()
|
||
h_tensor_detached = h_tensor_detached.reshape(h_tensor_detached.shape[0], -1, self.params.dim)
|
||
|
||
# 数据库更新逻辑与主计算图分离
|
||
with torch.no_grad():
|
||
|
||
# Compute shared downsampling layer once
|
||
shared_features = self.shared_downsample(h_tensor_detached)
|
||
|
||
# Get features from v path - now we output embedding-dimension vectors
|
||
z_v_features = self.downsample_v_specific(shared_features)
|
||
batch_z, seq_len, dim_z = z_v_features.shape
|
||
|
||
# Reshape to batch_size * knowledge_length, dim
|
||
z_v_flat = z_v_features.reshape(-1, dim_z)
|
||
|
||
# Direct token prediction - like the main language model head
|
||
token_logits = self.database_output(z_v_flat) # [batch_z * seq_len, vocab_size]
|
||
# Get token indices directly from logits
|
||
token_indices_flat = torch.argmax(token_logits, dim=-1)
|
||
token_indices = token_indices_flat.reshape(batch_z, -1)
|
||
|
||
# Process query path as before
|
||
z_q = self.downsample_q_specific(shared_features)
|
||
z_k = self.extract_db.q_to_k(z_q)
|
||
self.extract_db.updata_value(z_k, token_indices)
|
||
|
||
slice_indices = slice(-logits_to_keep, None) if isinstance(logits_to_keep, int) else logits_to_keep
|
||
logits = self.output(self.norm(h)[:, slice_indices, :])
|
||
aux_loss = sum(l.feed_forward.aux_loss for l in self.layers if isinstance(l.feed_forward, MOEFeedForward))
|
||
|
||
# 进一步简化，只保留必要的参数
|
||
output = CausalLMOutputWithPast(
|
||
logits=logits,
|
||
)
|
||
output.hidden_states = h
|
||
|
||
output.aux_loss = aux_loss
|
||
|
||
# 尝试添加其他属性（如果支持的话）
|
||
# try:
|
||
# output.hidden_states = h
|
||
# except:
|
||
# pass
|
||
|
||
return output
|
||
|
||
@torch.inference_mode()
|
||
def generate(self, input_ids, eos_token_id=2, max_new_tokens=1024, temperature=0.75, top_p=0.90,
|
||
stream=False, rp=1., pad_token_id=0, num_return_sequences=1, **args):
|
||
# 流式生成
|
||
if stream:
|
||
return self._stream(input_ids, eos_token_id, max_new_tokens, temperature, top_p, rp, **args)
|
||
|
||
# 直接生成
|
||
generated = []
|
||
for i in range(input_ids.size(0)):
|
||
non_pad = input_ids[i][input_ids[i] != pad_token_id].unsqueeze(0)
|
||
for _ in range(num_return_sequences):
|
||
out = self._stream(non_pad, eos_token_id, max_new_tokens, temperature, top_p, rp, **args)
|
||
tokens_list = [tokens[:, -1:] for tokens in out]
|
||
gen = torch.cat(tokens_list, dim=-1) if tokens_list else non_pad
|
||
full_sequence = torch.cat([non_pad, gen], dim=-1)
|
||
generated.append(full_sequence)
|
||
|
||
max_length = max(seq.size(1) for seq in generated)
|
||
generated = [
|
||
torch.cat(
|
||
[seq, torch.full((1, max_length - seq.size(1)), pad_token_id, dtype=seq.dtype, device=seq.device)],
|
||
dim=-1)
|
||
for seq in generated
|
||
]
|
||
output = torch.cat(generated, dim=0)
|
||
res = output.view(input_ids.size(0) * num_return_sequences, -1)
|
||
return res
|
||
|
||
def _stream(self, input_ids, eos_token_id, max_new_tokens, temperature, top_p, rp, **args):
|
||
start, first_seq = input_ids.shape[1], True
|
||
while input_ids.shape[1] < max_new_tokens - 1:
|
||
if first_seq:
|
||
out, first_seq = self(input_ids, **args), False
|
||
else:
|
||
out = self(input_ids[:, -1:], start_pos=input_ids.shape[1] - 1, **args)
|
||
logits = out.logits[:, -1, :]
|
||
logits[:, list(set(input_ids.tolist()[0]))] /= rp
|
||
logits /= (temperature + 1e-9)
|
||
if top_p is not None and top_p < 1.0:
|
||
sorted_logits, sorted_indices = torch.sort(logits, descending=True, dim=-1)
|
||
sorted_probs = F.softmax(sorted_logits, dim=-1)
|
||
cumulative_probs = torch.cumsum(sorted_probs, dim=-1)
|
||
sorted_indices_to_remove = cumulative_probs > top_p
|
||
sorted_indices_to_remove[:, 1:] = sorted_indices_to_remove[:, :-1].clone()
|
||
sorted_indices_to_remove[:, 0] = False
|
||
indices_to_remove = sorted_indices_to_remove.scatter(1, sorted_indices, sorted_indices_to_remove)
|
||
logits[indices_to_remove] = -float('Inf')
|
||
input_ids_next = torch.multinomial(F.softmax(logits, dim=-1), num_samples=1)
|
||
input_ids = torch.cat((input_ids, input_ids_next), dim=1)
|
||
yield input_ids[:, start:]
|
||
if input_ids_next.item() == eos_token_id:
|
||
break
|